So this is not a bug, please let me know if I need to adjust anything to indicate that.

Ah I was completely unaware of that limit, thank you! That's exactly what is happening.

I have a blueprint that is 102x102 with power poles at the corners, and it snaps to the 100x100 grid so that the large power poles overlap when I place the blueprint down multiple times.

When placing the blueprint, the poles which overlap sometimes fail to connect to the poles in the new blueprint ...