diff --git a/DbFirst.BlazorWebApp/Components/BandGridBase.cs b/DbFirst.BlazorWebApp/Components/BandGridBase.cs
index d8c4525..ef47bb6 100644
--- a/DbFirst.BlazorWebApp/Components/BandGridBase.cs
+++ b/DbFirst.BlazorWebApp/Components/BandGridBase.cs
@@ -132,13 +132,13 @@ public abstract class BandGridBase<TItem> : ComponentBase
         UpdateBandOptions();
     }
 
-    protected void RemoveBand(BandDefinition band)
+    protected async Task RemoveBand(BandDefinition band)
     {
         bandLayout.Bands.Remove(band);
         foreach (var key in columnBandAssignments.Where(p => p.Value == band.Id).Select(p => p.Key).ToList())
             columnBandAssignments.Remove(key);
         UpdateBandOptions();
-        SyncBandsFromAssignments();
+        await SyncBandsFromAssignments();
     }
 
     protected void UpdateBandCaption(BandDefinition band, string value)
@@ -147,19 +147,19 @@ public abstract class BandGridBase<TItem> : ComponentBase
         UpdateBandOptions();
     }
 
-    protected void UpdateColumnBand(string fieldName, string? bandId)
+    protected async Task UpdateColumnBand(string fieldName, string? bandId)
     {
         if (string.IsNullOrWhiteSpace(bandId))
             columnBandAssignments.Remove(fieldName);
         else
             columnBandAssignments[fieldName] = bandId;
-        SyncBandsFromAssignments();
+        await SyncBandsFromAssignments();
     }
 
     protected string GetColumnBand(string fieldName)
         => columnBandAssignments.TryGetValue(fieldName, out var bandId) ? bandId : string.Empty;
 
-    protected void SyncBandsFromAssignments()
+    protected async Task SyncBandsFromAssignments()
     {
         foreach (var band in bandLayout.Bands)
         {
@@ -168,7 +168,7 @@ public abstract class BandGridBase<TItem> : ComponentBase
                 .Select(c => c.FieldName)
                 .ToList();
         }
-        _ = InvokeAsync(StateHasChanged);
+        await InvokeAsync(StateHasChanged);
     }
 
     protected void UpdateBandOptions()
@@ -245,8 +245,8 @@ public abstract class BandGridBase<TItem> : ComponentBase
         if (!_dateFilterTemplates.TryGetValue(fieldName, out var template))
         {
             // EventCallbacks einmalig erstellen – stabile Referenzen über alle Renders
-            _fromCallbacks[fieldName] = EventCallback.Factory.Create<DateTime?>(this, (DateTime? v) => OnFilterFromChanged(fieldName, v));
-            _toCallbacks[fieldName] = EventCallback.Factory.Create<DateTime?>(this, (DateTime? v) => OnFilterToChanged(fieldName, v));
+            _fromCallbacks[fieldName] = EventCallback.Factory.Create<DateTime?>(this, async (DateTime? v) => await OnFilterFromChanged(fieldName, v));
+            _toCallbacks[fieldName] = EventCallback.Factory.Create<DateTime?>(this, async (DateTime? v) => await OnFilterToChanged(fieldName, v));
             template = BuildDateFilterTemplate(fieldName);
             _dateFilterTemplates[fieldName] = template;
         }
@@ -330,19 +330,19 @@ public abstract class BandGridBase<TItem> : ComponentBase
         else if (op.OperatorType == BinaryOperatorType.Less) to = dt.AddDays(-1);
     }
 
-    private void OnFilterFromChanged(string fieldName, DateTime? value)
+    private async Task OnFilterFromChanged(string fieldName, DateTime? value)
     {
         _filterFrom[fieldName] = value;
-        ApplyDateFilter(fieldName);
+        await ApplyDateFilter(fieldName);
     }
 
-    private void OnFilterToChanged(string fieldName, DateTime? value)
+    private async Task OnFilterToChanged(string fieldName, DateTime? value)
     {
         _filterTo[fieldName] = value;
-        ApplyDateFilter(fieldName);
+        await ApplyDateFilter(fieldName);
     }
 
-    private void ApplyDateFilter(string fieldName)
+    private async Task ApplyDateFilter(string fieldName)
     {
         var ops = new List<CriteriaOperator>();
         if (_filterFrom.TryGetValue(fieldName, out var from) && from.HasValue)
@@ -360,7 +360,7 @@ public abstract class BandGridBase<TItem> : ComponentBase
         gridRef?.SetFieldFilterCriteria(fieldName, criteria);
         if (_filterContexts.TryGetValue(fieldName, out var ctx))
             ctx.FilterCriteria = criteria;
-        _ = InvokeAsync(StateHasChanged);
+        await InvokeAsync(StateHasChanged);
     }
 
     protected void SetEditContext(EditContext context)