I have two iPads, one iPad 2 and one iPad 3. Both are at iOS 9.1. Curiously, the latest update (0.12.3 alpha says the PE, even though the "Affects Versions" menu only offers up to 0.12.2) killed multiplayer.

What "killed multiplayer" means: a world started on the iPad 3 doesn't show up in the iPad 2 as a multiplayer game. This used to work fine like last week.

I have checked both iPads, and the "Broadcast to LAN" is on in both. Both iPads can connect to the Internet fine.

More curiously: if the older iPad starts a different world, my iPhone can see that as a multiplayer game, but the newer iPad cannot see that. It's as if the newer iPad has been completely blocked from doing multiplayer.