diff --git a/common/commonspace/syncservice/mock_syncservice/mock_syncservice.go b/common/commonspace/syncservice/mock_syncservice/mock_syncservice.go
new file mode 100644
index 00000000..8438ab64
--- /dev/null
+++ b/common/commonspace/syncservice/mock_syncservice/mock_syncservice.go
@@ -0,0 +1,78 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/syncservice (interfaces: SyncClient)
+
+// Package mock_syncservice is a generated GoMock package.
+package mock_syncservice
+
+import (
+	reflect "reflect"
+
+	spacesyncproto "github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/spacesyncproto"
+	gomock "github.com/golang/mock/gomock"
+)
+
+// MockSyncClient is a mock of SyncClient interface.
+type MockSyncClient struct {
+	ctrl     *gomock.Controller
+	recorder *MockSyncClientMockRecorder
+}
+
+// MockSyncClientMockRecorder is the mock recorder for MockSyncClient.
+type MockSyncClientMockRecorder struct {
+	mock *MockSyncClient
+}
+
+// NewMockSyncClient creates a new mock instance.
+func NewMockSyncClient(ctrl *gomock.Controller) *MockSyncClient {
+	mock := &MockSyncClient{ctrl: ctrl}
+	mock.recorder = &MockSyncClientMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockSyncClient) EXPECT() *MockSyncClientMockRecorder {
+	return m.recorder
+}
+
+// BroadcastAsync mocks base method.
+func (m *MockSyncClient) BroadcastAsync(arg0 *spacesyncproto.ObjectSyncMessage) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "BroadcastAsync", arg0)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// BroadcastAsync indicates an expected call of BroadcastAsync.
+func (mr *MockSyncClientMockRecorder) BroadcastAsync(arg0 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "BroadcastAsync", reflect.TypeOf((*MockSyncClient)(nil).BroadcastAsync), arg0)
+}
+
+// SendAsync mocks base method.
+func (m *MockSyncClient) SendAsync(arg0 string, arg1 *spacesyncproto.ObjectSyncMessage) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "SendAsync", arg0, arg1)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// SendAsync indicates an expected call of SendAsync.
+func (mr *MockSyncClientMockRecorder) SendAsync(arg0, arg1 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "SendAsync", reflect.TypeOf((*MockSyncClient)(nil).SendAsync), arg0, arg1)
+}
+
+// SendSync mocks base method.
+func (m *MockSyncClient) SendSync(arg0 string, arg1 *spacesyncproto.ObjectSyncMessage) (*spacesyncproto.ObjectSyncMessage, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "SendSync", arg0, arg1)
+	ret0, _ := ret[0].(*spacesyncproto.ObjectSyncMessage)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// SendSync indicates an expected call of SendSync.
+func (mr *MockSyncClientMockRecorder) SendSync(arg0, arg1 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "SendSync", reflect.TypeOf((*MockSyncClient)(nil).SendSync), arg0, arg1)
+}
diff --git a/common/commonspace/syncservice/synchandler.go b/common/commonspace/syncservice/synchandler.go
index 3a0da9fd..0123cbff 100644
--- a/common/commonspace/syncservice/synchandler.go
+++ b/common/commonspace/syncservice/synchandler.go
@@ -1,3 +1,4 @@
+//go:generate mockgen -destination mock_syncservice/mock_syncservice.go github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/syncservice SyncClient
 package syncservice
 
 import (
@@ -31,16 +32,16 @@ func (s *syncHandler) HandleMessage(ctx context.Context, senderId string, msg *s
 	content := msg.GetContent()
 	switch {
 	case content.GetFullSyncRequest() != nil:
-		return s.HandleFullSyncRequest(ctx, senderId, content.GetFullSyncRequest(), msg)
+		return s.handleFullSyncRequest(ctx, senderId, content.GetFullSyncRequest(), msg)
 	case content.GetFullSyncResponse() != nil:
-		return s.HandleFullSyncResponse(ctx, senderId, content.GetFullSyncResponse(), msg)
+		return s.handleFullSyncResponse(ctx, senderId, content.GetFullSyncResponse(), msg)
 	case content.GetHeadUpdate() != nil:
-		return s.HandleHeadUpdate(ctx, senderId, content.GetHeadUpdate(), msg)
+		return s.handleHeadUpdate(ctx, senderId, content.GetHeadUpdate(), msg)
 	}
 	return nil
 }
 
-func (s *syncHandler) HandleHeadUpdate(
+func (s *syncHandler) handleHeadUpdate(
 	ctx context.Context,
 	senderId string,
 	update *spacesyncproto.ObjectHeadUpdate,
@@ -70,12 +71,14 @@ func (s *syncHandler) HandleHeadUpdate(
 			return err
 		}
 
-		// if we couldn't add all the changes
-		if len(update.Changes) != len(result.Added) {
-			fullRequest, err = s.prepareFullSyncRequest(objTree, update)
-			if err != nil {
-				return err
-			}
+		// if after the heads are equal, or we have them locally
+		if slice.UnsortedEquals(update.Heads, result.Heads) || objTree.HasChanges(update.Heads...) {
+			return nil
+		}
+
+		fullRequest, err = s.prepareFullSyncRequest(objTree, update)
+		if err != nil {
+			return err
 		}
 		return nil
 	}()
@@ -87,7 +90,7 @@ func (s *syncHandler) HandleHeadUpdate(
 	return
 }
 
-func (s *syncHandler) HandleFullSyncRequest(
+func (s *syncHandler) handleFullSyncRequest(
 	ctx context.Context,
 	senderId string,
 	request *spacesyncproto.ObjectFullSyncRequest,
@@ -133,7 +136,7 @@ func (s *syncHandler) HandleFullSyncRequest(
 		spacesyncproto.WrapFullResponse(fullResponse, header, msg.TreeId, msg.TrackingId))
 }
 
-func (s *syncHandler) HandleFullSyncResponse(
+func (s *syncHandler) handleFullSyncResponse(
 	ctx context.Context,
 	senderId string,
 	response *spacesyncproto.ObjectFullSyncResponse,
diff --git a/common/commonspace/syncservice/synchandler_test.go b/common/commonspace/syncservice/synchandler_test.go
new file mode 100644
index 00000000..dc145017
--- /dev/null
+++ b/common/commonspace/syncservice/synchandler_test.go
@@ -0,0 +1,58 @@
+package syncservice
+
+import (
+	"context"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/cache"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/cache/mock_cache"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/spacesyncproto"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/common/commonspace/syncservice/mock_syncservice"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/pkg/acl/tree"
+	mock_tree "github.com/anytypeio/go-anytype-infrastructure-experiments/pkg/acl/tree/mock_objecttree"
+	"github.com/anytypeio/go-anytype-infrastructure-experiments/pkg/acl/treechangeproto"
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/require"
+	"testing"
+)
+
+type treeContainer struct {
+	objTree tree.ObjectTree
+}
+
+func (t treeContainer) Tree() tree.ObjectTree {
+	return t.objTree
+}
+
+func TestSyncHandler_HandleMessage(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	ctx := context.Background()
+	spaceId := "spaceId"
+	cacheMock := mock_cache.NewMockTreeCache(ctrl)
+	syncClientMock := mock_syncservice.NewMockSyncClient(ctrl)
+	objectTreeMock := mock_tree.NewMockObjectTree(ctrl)
+
+	syncHandler := newSyncHandler(spaceId, cacheMock, syncClientMock)
+	treeId := "treeId"
+	senderId := "senderId"
+	chWithId := &treechangeproto.RawTreeChangeWithId{}
+	headUpdate := &spacesyncproto.ObjectHeadUpdate{
+		Heads:        []string{"h1"},
+		Changes:      []*treechangeproto.RawTreeChangeWithId{chWithId},
+		SnapshotPath: []string{"h1"},
+	}
+	msg := spacesyncproto.WrapHeadUpdate(headUpdate, chWithId, treeId, "")
+	cacheMock.EXPECT().
+		GetTree(gomock.Any(), spaceId, treeId).
+		Return(cache.TreeResult{
+			Release:       func() {},
+			TreeContainer: treeContainer{objectTreeMock},
+		}, nil)
+	objectTreeMock.EXPECT().Lock()
+	objectTreeMock.EXPECT().Heads().Return([]string{"h2"})
+	objectTreeMock.EXPECT().AddRawChanges(gomock.Any(), gomock.Eq([]*treechangeproto.RawTreeChangeWithId{chWithId})).
+		Return(tree.AddResult{}, nil)
+	objectTreeMock.EXPECT().Unlock()
+	err := syncHandler.HandleMessage(ctx, senderId, msg)
+	require.NoError(t, err)
+}
diff --git a/pkg/acl/storage/inmemory.go b/pkg/acl/storage/inmemory.go
index 6ddbea57..487caa04 100644
--- a/pkg/acl/storage/inmemory.go
+++ b/pkg/acl/storage/inmemory.go
@@ -87,6 +87,11 @@ func NewInMemoryTreeStorage(
 	}, nil
 }
 
+func (t *inMemoryTreeStorage) HasChange(ctx context.Context, id string) (bool, error) {
+	_, exists := t.changes[id]
+	return exists, nil
+}
+
 func (t *inMemoryTreeStorage) ID() (string, error) {
 	t.RLock()
 	defer t.RUnlock()
diff --git a/pkg/acl/storage/mock_storage/mock_storage.go b/pkg/acl/storage/mock_storage/mock_storage.go
index 5fff6944..f20bf468 100644
--- a/pkg/acl/storage/mock_storage/mock_storage.go
+++ b/pkg/acl/storage/mock_storage/mock_storage.go
@@ -162,6 +162,21 @@ func (mr *MockTreeStorageMockRecorder) GetRawChange(arg0, arg1 interface{}) *gom
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetRawChange", reflect.TypeOf((*MockTreeStorage)(nil).GetRawChange), arg0, arg1)
 }
 
+// HasChange mocks base method.
+func (m *MockTreeStorage) HasChange(arg0 context.Context, arg1 string) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "HasChange", arg0, arg1)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// HasChange indicates an expected call of HasChange.
+func (mr *MockTreeStorageMockRecorder) HasChange(arg0, arg1 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "HasChange", reflect.TypeOf((*MockTreeStorage)(nil).HasChange), arg0, arg1)
+}
+
 // Heads mocks base method.
 func (m *MockTreeStorage) Heads() ([]string, error) {
 	m.ctrl.T.Helper()
diff --git a/pkg/acl/storage/treestorage.go b/pkg/acl/storage/treestorage.go
index a9c98f1d..25b91e46 100644
--- a/pkg/acl/storage/treestorage.go
+++ b/pkg/acl/storage/treestorage.go
@@ -13,6 +13,7 @@ type TreeStorage interface {
 
 	AddRawChange(change *treechangeproto.RawTreeChangeWithId) error
 	GetRawChange(ctx context.Context, id string) (*treechangeproto.RawTreeChangeWithId, error)
+	HasChange(ctx context.Context, id string) (bool, error)
 }
 
 type TreeStorageCreatorFunc = func(payload TreeStorageCreatePayload) (TreeStorage, error)
diff --git a/pkg/acl/tree/mock_objecttree/mock_objecttree.go b/pkg/acl/tree/mock_objecttree/mock_objecttree.go
index a4eac719..70afa9d4 100644
--- a/pkg/acl/tree/mock_objecttree/mock_objecttree.go
+++ b/pkg/acl/tree/mock_objecttree/mock_objecttree.go
@@ -116,18 +116,22 @@ func (mr *MockObjectTreeMockRecorder) DebugDump() *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "DebugDump", reflect.TypeOf((*MockObjectTree)(nil).DebugDump))
 }
 
-// HasChange mocks base method.
-func (m *MockObjectTree) HasChange(arg0 string) bool {
+// HasChanges mocks base method.
+func (m *MockObjectTree) HasChanges(arg0 ...string) bool {
 	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "HasChange", arg0)
+	varargs := []interface{}{}
+	for _, a := range arg0 {
+		varargs = append(varargs, a)
+	}
+	ret := m.ctrl.Call(m, "HasChanges", varargs...)
 	ret0, _ := ret[0].(bool)
 	return ret0
 }
 
-// HasChange indicates an expected call of HasChange.
-func (mr *MockObjectTreeMockRecorder) HasChange(arg0 interface{}) *gomock.Call {
+// HasChanges indicates an expected call of HasChanges.
+func (mr *MockObjectTreeMockRecorder) HasChanges(arg0 ...interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "HasChange", reflect.TypeOf((*MockObjectTree)(nil).HasChange), arg0)
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "HasChanges", reflect.TypeOf((*MockObjectTree)(nil).HasChanges), arg0...)
 }
 
 // Header mocks base method.
diff --git a/pkg/acl/tree/objecttree.go b/pkg/acl/tree/objecttree.go
index 47305d23..9e6323aa 100644
--- a/pkg/acl/tree/objecttree.go
+++ b/pkg/acl/tree/objecttree.go
@@ -43,7 +43,7 @@ type ObjectTree interface {
 	Header() *treechangeproto.RawTreeChangeWithId
 	Heads() []string
 	Root() *Change
-	HasChange(string) bool
+	HasChanges(...string) bool
 	DebugDump() (string, error)
 
 	Iterate(convert ChangeConvertFunc, iterate ChangeIterateFunc) error
@@ -76,7 +76,7 @@ type objectTree struct {
 
 	// buffers
 	difSnapshotBuf  []*treechangeproto.RawTreeChangeWithId
-	tmpChangesBuf   []*Change
+	newChangesBuf   []*Change
 	newSnapshotsBuf []*Change
 	notSeenIdxBuf   []int
 
@@ -227,7 +227,7 @@ func (ot *objectTree) AddRawChanges(ctx context.Context, rawChanges ...*treechan
 
 func (ot *objectTree) addRawChanges(ctx context.Context, rawChanges ...*treechangeproto.RawTreeChangeWithId) (addResult AddResult, err error) {
 	// resetting buffers
-	ot.tmpChangesBuf = ot.tmpChangesBuf[:0]
+	ot.newChangesBuf = ot.newChangesBuf[:0]
 	ot.notSeenIdxBuf = ot.notSeenIdxBuf[:0]
 	ot.difSnapshotBuf = ot.difSnapshotBuf[:0]
 	ot.newSnapshotsBuf = ot.newSnapshotsBuf[:0]
@@ -247,20 +247,21 @@ func (ot *objectTree) addRawChanges(ctx context.Context, rawChanges ...*treechan
 		if _, exists := ot.tree.attached[ch.Id]; exists {
 			continue
 		}
-		if _, exists := ot.tree.unAttached[ch.Id]; exists {
-			continue
-		}
 
 		var change *Change
-		change, err = ot.changeBuilder.ConvertFromRaw(ch, true)
-		if err != nil {
-			return
+		if unAttached, exists := ot.tree.unAttached[ch.Id]; exists {
+			change = unAttached
+		} else {
+			change, err = ot.changeBuilder.ConvertFromRaw(ch, true)
+			if err != nil {
+				return
+			}
 		}
 
 		if change.IsSnapshot {
 			ot.newSnapshotsBuf = append(ot.newSnapshotsBuf, change)
 		}
-		ot.tmpChangesBuf = append(ot.tmpChangesBuf, change)
+		ot.newChangesBuf = append(ot.newChangesBuf, change)
 		ot.notSeenIdxBuf = append(ot.notSeenIdxBuf, idx)
 	}
 
@@ -274,6 +275,106 @@ func (ot *objectTree) addRawChanges(ctx context.Context, rawChanges ...*treechan
 		return
 	}
 
+	rollback := func(changes []*Change) {
+		for _, ch := range changes {
+			if _, exists := ot.tree.attached[ch.Id]; exists {
+				delete(ot.tree.attached, ch.Id)
+			}
+		}
+	}
+
+	// checks if we need to go to database
+	isOldSnapshot := func(ch *Change) bool {
+		if ch.SnapshotId == ot.tree.RootId() {
+			return false
+		}
+		for _, sn := range ot.newSnapshotsBuf {
+			// if change refers to newly received snapshot
+			if ch.SnapshotId == sn.Id {
+				return false
+			}
+		}
+		return true
+	}
+
+	shouldRebuildFromStorage := false
+	// checking if we have some changes with different snapshot and then rebuilding
+	for idx, ch := range ot.newChangesBuf {
+		if isOldSnapshot(ch) {
+			var exists bool
+			// checking if it exists in the storage, if yes, then at some point it was added to the tree
+			// thus we don't need to look at this change
+			exists, err = ot.treeStorage.HasChange(ctx, ch.Id)
+			if err != nil {
+				return
+			}
+			if exists {
+				// marking as nil to delete after
+				ot.newChangesBuf[idx] = nil
+				continue
+			}
+			// we haven't seen the change, and it refers to old snapshot, so we should rebuild
+			shouldRebuildFromStorage = true
+		}
+	}
+	// discarding all previously seen changes
+	ot.newChangesBuf = discardFromSlice(ot.newChangesBuf, func(ch *Change) bool { return ch == nil })
+
+	if shouldRebuildFromStorage {
+		err = ot.rebuildFromStorage(ot.newChangesBuf)
+		if err != nil {
+			// rebuilding without new changes
+			ot.rebuildFromStorage(nil)
+			return
+		}
+		addResult, err = ot.createAddResult(prevHeadsCopy, Rebuild, nil, rawChanges)
+		if err != nil {
+			// that means that some unattached changes were somehow corrupted in memory
+			// this shouldn't happen but if that happens, then rebuilding from storage
+			ot.rebuildFromStorage(nil)
+			return
+		}
+		return
+	}
+
+	// normal mode of operation, where we don't need to rebuild from database
+	mode, treeChangesAdded := ot.tree.Add(ot.newChangesBuf...)
+	switch mode {
+	case Nothing:
+		addResult = AddResult{
+			OldHeads: prevHeadsCopy,
+			Heads:    prevHeadsCopy,
+			Mode:     mode,
+		}
+		return
+
+	default:
+		// we need to validate only newly added changes
+		err = ot.validateTree(treeChangesAdded)
+		if err != nil {
+			rollback(treeChangesAdded)
+			err = ErrHasInvalidChanges
+			return
+		}
+		addResult, err = ot.createAddResult(prevHeadsCopy, mode, treeChangesAdded, rawChanges)
+		if err != nil {
+			// that means that some unattached changes were somehow corrupted in memory
+			// this shouldn't happen but if that happens, then rebuilding from storage
+			ot.rebuildFromStorage(nil)
+			return
+		}
+		return
+	}
+	return
+}
+
+func (ot *objectTree) createAddResult(oldHeads []string, mode Mode, treeChangesAdded []*Change, rawChanges []*treechangeproto.RawTreeChangeWithId) (addResult AddResult, err error) {
+	headsCopy := func() []string {
+		newHeads := make([]string, 0, len(ot.tree.Heads()))
+		newHeads = append(newHeads, ot.tree.Heads()...)
+		return newHeads
+	}
+
 	// returns changes that we added to the tree as attached this round
 	// they can include not only the changes that were added now,
 	// but also the changes that were previously in the tree
@@ -313,88 +414,16 @@ func (ot *objectTree) addRawChanges(ctx context.Context, rawChanges ...*treechan
 		return
 	}
 
-	rollback := func(changes []*Change) {
-		for _, ch := range changes {
-			if _, exists := ot.tree.attached[ch.Id]; exists {
-				delete(ot.tree.attached, ch.Id)
-			}
-		}
-	}
-
-	// checks if we need to go to database
-	isOldSnapshot := func(ch *Change) bool {
-		if ch.SnapshotId == ot.tree.RootId() {
-			return false
-		}
-		for _, sn := range ot.newSnapshotsBuf {
-			// if change refers to newly received snapshot
-			if ch.SnapshotId == sn.Id {
-				return false
-			}
-		}
-		return true
-	}
-
-	// checking if we have some changes with different snapshot and then rebuilding
-	for _, ch := range ot.tmpChangesBuf {
-		if isOldSnapshot(ch) {
-			err = ot.rebuildFromStorage(ot.tmpChangesBuf)
-			if err != nil {
-				// rebuilding without new changes
-				ot.rebuildFromStorage(nil)
-				return
-			}
-			var added []*treechangeproto.RawTreeChangeWithId
-			added, err = getAddedChanges(nil)
-			// we shouldn't get any error in this case
-			if err != nil {
-				panic(err)
-			}
-
-			addResult = AddResult{
-				OldHeads: prevHeadsCopy,
-				Heads:    headsCopy(),
-				Added:    added,
-				Mode:     Rebuild,
-			}
-			return
-		}
-	}
-
-	// normal mode of operation, where we don't need to rebuild from database
-	mode, treeChangesAdded := ot.tree.Add(ot.tmpChangesBuf...)
-	switch mode {
-	case Nothing:
-		addResult = AddResult{
-			OldHeads: prevHeadsCopy,
-			Heads:    prevHeadsCopy,
-			Mode:     mode,
-		}
+	var added []*treechangeproto.RawTreeChangeWithId
+	added, err = getAddedChanges(treeChangesAdded)
+	if err != nil {
 		return
-
-	default:
-		// we need to validate only newly added changes
-		err = ot.validateTree(treeChangesAdded)
-		if err != nil {
-			rollback(treeChangesAdded)
-			err = ErrHasInvalidChanges
-			return
-		}
-		var added []*treechangeproto.RawTreeChangeWithId
-		added, err = getAddedChanges(treeChangesAdded)
-		if err != nil {
-			// that means that some unattached changes were somehow corrupted in memory
-			// this shouldn't happen but if that happens, then rebuilding from storage
-			ot.rebuildFromStorage(nil)
-			return
-		}
-
-		addResult = AddResult{
-			OldHeads: prevHeadsCopy,
-			Heads:    headsCopy(),
-			Added:    added,
-			Mode:     mode,
-		}
+	}
+	addResult = AddResult{
+		OldHeads: oldHeads,
+		Heads:    headsCopy(),
+		Added:    added,
+		Mode:     mode,
 	}
 	return
 }
@@ -441,9 +470,28 @@ func (ot *objectTree) IterateFrom(id string, convert ChangeConvertFunc, iterate
 	return
 }
 
-func (ot *objectTree) HasChange(s string) bool {
-	_, attachedExists := ot.tree.attached[s]
-	return attachedExists
+func (ot *objectTree) HasChanges(chs ...string) bool {
+	hasChange := func(s string) bool {
+		_, attachedExists := ot.tree.attached[s]
+		if attachedExists {
+			return attachedExists
+		}
+
+		has, err := ot.treeStorage.HasChange(context.Background(), s)
+		if err != nil {
+			return false
+		}
+
+		return has
+	}
+
+	for _, ch := range chs {
+		if !hasChange(ch) {
+			return false
+		}
+	}
+
+	return true
 }
 
 func (ot *objectTree) Heads() []string {
diff --git a/pkg/acl/tree/objecttreefactory.go b/pkg/acl/tree/objecttreefactory.go
index 61631412..1db77908 100644
--- a/pkg/acl/tree/objecttreefactory.go
+++ b/pkg/acl/tree/objecttreefactory.go
@@ -104,7 +104,7 @@ func buildObjectTree(deps objectTreeDeps) (ObjectTree, error) {
 		rawChangeLoader: deps.rawChangeLoader,
 		tree:            nil,
 		keys:            make(map[uint64]*symmetric.Key),
-		tmpChangesBuf:   make([]*Change, 0, 10),
+		newChangesBuf:   make([]*Change, 0, 10),
 		difSnapshotBuf:  make([]*treechangeproto.RawTreeChangeWithId, 0, 10),
 		notSeenIdxBuf:   make([]int, 0, 10),
 		newSnapshotsBuf: make([]*Change, 0, 10),