Sorry for the delay, been busy! It was the same layout as going over, not a completely flat bed but adequate for my needs. No extra "mattress" as per Emirates, but I did sleep. New A330's with flat beds are meant to be in service this month.
I had to check my bag through to Singapore so I only had my carrry on in Sri lanka for 24 hours, didn't need much else.
The schedule shows the following: A340's are used from Colombo to Heathrow leaving at 02:30 and arriving at 08:45 and leaves Heathrow at 12:45 and arrives in Colombo at 04:30.
Mine left at 13:00 and arrived at about 20:00. Coming back it was similar, left at about 21:00 and got into Colombo at about 13:00, the schedule also shows these flight as "equipment varies".
Sri lankan uses BA's Lounges at terminal 3.
I'd fly them again although I'm sure my expectations are lower than some on this forum. About the only thing I didn't find ok was that we arrived just after a PIA flight from Lahore, hence the queues at immigration in Heathrow were quite lenghty, I can't blame Sri lankan for that though.
Thanks again to Defurax for posting the original information about their sale. SC's were the same for each leg, Singapore to Colombo and Colombo to London, 80 each, so all in all it was a good haul.
Just did a bit of a search and found this fb page:
https://www.facebook.com/ULCabinCrew/timeline?ref=page_internal
This is definitely not the seat I had!
https://www.facebook.com/ULCabinCre...0.1415688479./754123211304001/?type=3&theater