This is not the case at MAN if you hold a boarding pass.

It depends where you arrive. If you disembark at gates 144-148, there is a TRANSFER sign in the waiting area for these gates that directs you upstairs to the main lounge (you'll walk past gates 143 and 142 on the upper level as you head to the lounge).

If you arrive at gates 142 or 143, you'll be directed down some stairs and at the bottom you would normally turn left to baggage reclaim and arrivals. Instead turn right and head down towards the waiting area for gates 144-148 and then follow ther above instructions.

If you arrive at gate 141, it's a mess and you'll probably be directed down into baggage reclasim and you'll have to exit and re-enter through security.