Rails aren't always powered correctly

Rails sometimes aren't powered correctly and large sections of rail can be left unpowered.

Steps to reproduce

1. Build this:
2. Be sure to put the lever on the side of the block toward the front of the picture, not on the top of the block.

Expected results

The farther away block in the picture activates 8 more rails beyond it.

Actual results

The blocks beyond the farther away block are not activated. However, if you put the lever on top of the closer block instead, or if you place a rail next where the lever is in the picture, then the farther away block does activate 8 more rails beyond it.

Notes

Related to MCPE-81981

I believe this is a problem with the power sources calculating what they're powering, not the rails, as with 2 power sources it works.

Note that this is not related to chunk borders.