Originally Posted by Globe Trots
I've never done a transit at LHR before, so I'd like to ask if I can get from T2 to T3 without going thru customs (the queues can be quite insane for non-EU citizens!
I'm not quite sure what your query has to do with BA, but I suppose we have expertise on transfers if not on T3.
Yes, you can do this entirely airside. On arrival at T2, follow the signs for Flight Connections, Terminal 3. This will route you to the Flight Connections Centre where you'll clear security and then check-in with EK at the transfer desks in the FCC. Then you'll be routed downstairs onto a bus to take you to T3. No immigration involved.
ISTR that there was a "quiet area" upstairs in the T3 departures lounge, but this may have been a temporary thing. Otherwise, you may want to try a pay lounge (the Servisair lounge, perhaps?) to use. But if you don't want to exit to landside, then your other options are pretty limited at T3. Perhaps a loooong lunch in Chez Gerard.
Originally Posted by Globe Trots
... but can I get my checked-in luggage transferred across without having to physically collect the bags (once again, the point is to avoid customs).
If AF will through-tag your bag to SIN, your bag will be transferred automatically at LHR. Some airlines won't always through-tag bags if you're travelling on two separate tickets, but this will depend on AF's policies.