Originally Posted by
KARFA
I think you have a few options. One is to just go through immigration and head over to T2 (tube or Heathrow Express) to use the priority pass arrivals lounge
There is another variant of this (as noted in your post 10) - take the flight connections bus to T2 airside and go through immigration there for the PP Arrivals lounge. Could be the quickest option especially if arriving at T5B.