Originally Posted by
UKtravelbear
The process will depend if you have checked bags or not.
Arrivals and departures are separated so you’ll be directed to the UK Border and the airside connection route..
No checked bags.
Ok so it sounds like we may need to clear passport control first, then attempt to re-enter T3 through security and hope they let us in. If not, then clear security in T5 and then do the T5-T3 dance outlined previously.