Steps to reproduce

1. Create a world with the Redstone Experiment enabled
2. Place lever or button on the floor powering a rs line with two conflicting pistons underneath (see video)

2024-08-16 00-41-51.mp4

What I expected to happen

The piston which is "front" in respect to the lever's facing direction is updated first, like it already happens with wire:
2024-08-16 00-53-40.mp4

Or with wall levers:
2024-08-16 01-11-54 (1).mp4

What actually happened

The update order behaved randomly

Further info

Levers and buttons on floors and ceilings can be rotated in all 4 cardinal directions with unique block states.

Buttons have very little visual difference between north and south as well as west and east. You can see the dark line on the wooden button to be different, and the texture on the stone button to be mirrored as well, if you look closely:

This might be intentional to make builds not rely on the facing direction of a button when copying from a video, etc.