I have been using LHR for overnight connections on flights to and from the US a decent bit. With priority check-in and priority security screening at LHR to get airside at LHR, it’s been fine enough for me at T3 even when otherwise I was being told to expect worse — with the rush with lots of US flights. Is LHR T3 priority screening (to get airside) much worse in the late afternoon and evening?

I haven’t had a transit bag end up delayed at LHR yet this year. However last quarter at LHR, I’ve had my personal record long European wait to board a bus to disembark a landed flight. Substituting away from BA is better for me at LHR.