In message , Martin
Whelton writes
Do we know when construction work is due to start on the Piccadilly
extension to Terminal 5 as I understand that tunneling work was due to
be finished by next year. I also understand that Terminal 4 would be
temporaily closed during the construction period.

Tunnelling is well under way and I believe the station box is all but
finished.

Plans are advanced for the closure of the T4 loop to allow the T5
extension to be connected. I think the latest plan is around December.
I'll try and confirm today at work, but I think we're looking at about a
two year closure.
--
Steve Fitzgerald has now left the building.
You will find him in London's Docklands, E16, UK
(please use the reply to address for email)