If you use cloth diapers and disposables, what do you do about the car seat harness?

Babies wear cloth diapers on our short trips out but on longer trips (out of town) we put the babies in disposables.

As you know, there is more bum in cloth diapers.

I know the harness holes should be at or below their shoulders.

So I should measure and adjust their harness when they are in disposables so they are the shortest sitting position, right? Or do you rethread the harness every time? (Does anyone actually do that?)

If I use their disposable diapers height to adjust the straps, when they use cloth diapers, they are a bit higher up.

Is that any more dangerous? Probably should ask a CPST about this. Waiting for approval into the Car Seat for littles group.

We always make sure the straps pass the pinch test. Just wondering if that few cm affect the safety.

I found this through Fluff love but doesn't say anything about the safety of going from harness height of a disposable diaper to cloth.