Since 1.18 it has been established that the expected behaviour for rails and their neighbour updates should always be in the order of the furthest rail from the power source sending neighbour updates to surrounding redstone components first. However snapshot 25w02a has introduced a different behaviour for configurations of rail where there is a slope. In this case the rail at the top of the slope updates first and the sloped rail below is updated second despite being further from the power source.

The attached sceenshot gives a simple test setup demonstrating the problem.

Expected behaviour: the command blocks execute their commands in the order 1,2

Observed behaviour: the command blocks execute their commands in the order 2,1