I have a 2x2 Server that works perfectly fine - except one thing:
Admin Commands.
The home islands is in A1, all commands work fine on that server.
If your travel to A2, B1 or B2 - many admin commands do not work: like ForceTame or DoTame and most animal commands - except Kill; that works.
Does each server need (or require) a home island to work properly? it's the only difference between A1 and any of the others.