I went through T3 the other day a Friday at 5pm. the fast track experience was just that fast. BA check in has reverted to Zone G not sure why it moved to Zone D and back again.

BA Galleries lounge was busy but not as rammed as T5, did a bit of lounge hopping too, not overly impressed with the noodles in CX (but people rave about them), wifi in Admirals Club fantastic but food not as good as usual was just tea and nibbles normally their food is pretty good. For the first time had a gate as opposed to a bus. Border control and luggage delivery very much better than T5 in my opinion.. and I was disappointed when the Prague flights moved to T3 as I liked T5.