Have I missed rule change

When a player receives medical attention on pitch, usually has to go off to be called back on, noticed today on 3 occasions didn't have to..

Can stay on if opponent booked. Happened later when Peltier stayed on. New this season.

Can stay on if opponent booked. Happened later when Peltier stayed on. New this season.

Didn't know that

Also was it me today or was the PA system stupidly loud before the game?

It's always funny when the crowd start booing and chanting "you don't know what you're doing" when they have no idea that the rule has changed.

Same when offside free-kicks are taken from the opponents half because it's where the player touches the ball that it's taken from now.