Differing window heights over bench

[Chrisdespo]

Hi Guys and Girls I’m new to this forum, just installed new cabinets in kitchen and now starting tile splashback there is a difference in height between the two widows of around 15mm. I’m looking for a bit of advise on weather to drop the bottom of the architrave that is high or add a thin strip of timber or do it by having one tile hard up under low sill and a little wider grout line on the one under the higher sill. Any advice would be greatly appreciated