diff --git a/lib/selectors/socket-selectors.js b/lib/selectors/socket-selectors.js
--- a/lib/selectors/socket-selectors.js
+++ b/lib/selectors/socket-selectors.js
@@ -147,32 +147,20 @@
           const hashResults: { [string]: boolean } = {};
           for (const key in serverRequest.hashesToCheck) {
             const expectedHashValue = serverRequest.hashesToCheck[key];
-            let hashValue;
             const [specKey, id] = key.split('|');
-            if (id) {
-              hashValue = specPerInnerHashKey[specKey]?.getInfoHash(
-                id,
-                keyserverID,
-              );
-            } else {
-              hashValue = specsPerHashKey[specKey]?.getAllInfosHash(
-                query,
-                keyserverID,
-              );
-            }
+            const spec = id
+              ? specPerInnerHashKey[specKey]
+              : specsPerHashKey[specKey];
 
-            // If hashValue values is null then we are still calculating
-            // the hashes in the background. In this case we return true
-            // to skip this state check. Future state checks (after the hash
-            // calculation complete) will be handled normally.
-            // Another case when this is null is when we are handling state
-            // sync with a non-authoritative keyserver. We don't want to sync
-            // user store and current user info with such keyservers.
-            if (!hashValue) {
+            if (!spec?.canSyncState(keyserverID)) {
               hashResults[key] = true;
-            } else {
-              hashResults[key] = expectedHashValue === hashValue;
+              continue;
             }
+
+            const hashValue = id
+              ? spec?.getInfoHash(id, keyserverID)
+              : spec?.getAllInfosHash(query, keyserverID);
+            hashResults[key] = expectedHashValue === hashValue;
           }
 
           const { failUnmentioned } = serverRequest;
diff --git a/lib/shared/state-sync/current-user-state-sync-spec.js b/lib/shared/state-sync/current-user-state-sync-spec.js
--- a/lib/shared/state-sync/current-user-state-sync-spec.js
+++ b/lib/shared/state-sync/current-user-state-sync-spec.js
@@ -24,6 +24,8 @@
         return hash(currentUserInfo);
       },
       getIDs: () => ([]: string[]),
+      canSyncState: (keyserverID: string) =>
+        keyserverID === authoritativeKeyserverID(),
     }),
   );
 
diff --git a/lib/shared/state-sync/entries-state-sync-spec.js b/lib/shared/state-sync/entries-state-sync-spec.js
--- a/lib/shared/state-sync/entries-state-sync-spec.js
+++ b/lib/shared/state-sync/entries-state-sync-spec.js
@@ -42,6 +42,7 @@
       getEntryInfosHash(entryInfos, calendarQuery, keyserverID),
     getIDs: (calendarQuery: CalendarQuery, keyserverID: string) =>
       getEntryIDs(entryInfos, calendarQuery, keyserverID),
+    canSyncState: () => true,
   }),
 );
 
diff --git a/lib/shared/state-sync/state-sync-spec.js b/lib/shared/state-sync/state-sync-spec.js
--- a/lib/shared/state-sync/state-sync-spec.js
+++ b/lib/shared/state-sync/state-sync-spec.js
@@ -24,12 +24,21 @@
 
 // All ids specified here (getInfoHash and getIDs) are server ids.
 // E.g. in the case of threadStore or entryStore the keyserver prefix
-// needs to be handled additionaly
+// needs to be handled additionally
 export type BoundStateSyncSpec<Infos, Info, Inconsistencies> = {
   // If these function depend on background hashing that is still not complete
   // they should return  null, to indicate that the hashes aren't available yet
   +getInfoHash: (id: string, keyserverID: string) => ?number,
   +getAllInfosHash: (query: CalendarQuery, keyserverID: string) => ?number,
   +getIDs: (query: CalendarQuery, keyserverID: string) => ?Array<string>,
+  // This function is used to check if we can sync the state.
+  // Currently, there are two cases where we can't sync the state:
+  // 1. When background thread hashing is still in progress
+  // 2. When a non-authoritative keyserver attempts a state sync of UserStore
+  //   or CurrentUserInfo
+  // If we can't do a state sync, we're informing a keyserver that all
+  // the hashes are correct. Later, the keyserver will attempt a state sync
+  // again.
+  +canSyncState: (keyserverID: string) => boolean,
   ...StateSyncSpec<Infos, Info, Inconsistencies>,
 };
diff --git a/lib/shared/state-sync/threads-state-sync-spec.js b/lib/shared/state-sync/threads-state-sync-spec.js
--- a/lib/shared/state-sync/threads-state-sync-spec.js
+++ b/lib/shared/state-sync/threads-state-sync-spec.js
@@ -51,6 +51,7 @@
             .filter(id => extractKeyserverIDFromID(id) === keyserverID)
             .map(id => id.split('|')[1])
       : () => null,
+    canSyncState: () => threadHashingComplete,
   }),
 );
 
diff --git a/lib/shared/state-sync/users-state-sync-spec.js b/lib/shared/state-sync/users-state-sync-spec.js
--- a/lib/shared/state-sync/users-state-sync-spec.js
+++ b/lib/shared/state-sync/users-state-sync-spec.js
@@ -42,6 +42,8 @@
       }
       return Object.keys(userInfos);
     },
+    canSyncState: (keyserverID: string) =>
+      keyserverID === authoritativeKeyserverID(),
   }),
 );