Try this link:
http://www.mod.uk/dpa/projects/
Re FSTA - the choice seems to be between the Boeing 767 and the Airbus A330-200. As the project is at a sensitive commercial stage, I won't comment on which is the preferred option to those who fly current tankers.
However:
KC-767 - Lots of orders from USA, Italy and Japan.
A330-200K - No orders.