diff --git a/internal/app/replication.go b/internal/app/replication.go
index 69f1fe30..b7f6f32d 100644
--- a/internal/app/replication.go
+++ b/internal/app/replication.go
@@ -41,7 +41,7 @@ func (app *App) MarkReplicationRunning(node *mysql.Node, channel string) {
 		newGtidSet := gtids.ParseGtidSet(status.GetExecutedGtidSet())
 		oldGtidSet := gtids.ParseGtidSet(replState.LastGTIDExecuted)
 
-		if !gtids.IsSlaveBehindOrEqual(newGtidSet, oldGtidSet) {
+		if gtids.IsSlaveAhead(newGtidSet, oldGtidSet) {
 			delete(app.replRepairState, key)
 		}
 	}
diff --git a/internal/app/util.go b/internal/app/util.go
index b3b54548..6a2feca3 100644
--- a/internal/app/util.go
+++ b/internal/app/util.go
@@ -226,7 +226,8 @@ func isSlavePermanentlyLost(sstatus mysql.ReplicaStatus, masterGtidSet gtids.GTI
 		return true
 	}
 	slaveGtidSet := gtids.ParseGtidSet(sstatus.GetExecutedGtidSet())
-	return !gtids.IsSlaveBehindOrEqual(slaveGtidSet, masterGtidSet)
+	// TODO: why ahead = lost?..
+	return gtids.IsSlaveAhead(slaveGtidSet, masterGtidSet)
 }
 
 func validatePriority(priority *int64) error {