Need Help With Loop Until in VBA

Maybe:

Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Range("A1")) Is Nothing Then
    If Target.Value >= Target.Offset(, 1).Value Then Exit Sub
    If Target.Value < Target.Offset(, 1).Value Then
    Target.Value = Target.Value + 0.05
    End If
End If
End Sub

Not really getting your point? Why not just A1 = B1. Or maybe I'm misunderstanding you.