N1120a, it appears we were both correct. HEX
have ordered 4 more units to cover the stopping service, and they will maintain the trains. However, between Paddington and Hayes, the train will operate as a domestic service and fGWL will reap the rewards; between Hayes and Heathrow HEX
(ie BAA) will get the fares. Quite what involvement fGWL have is unclear, but perhaps they will provide on-board staff on those services only.
Jupiters... I think you mean Junipers.
The Waterloo/Reading connection is designed for Reading travellers, ie from the west, not from Waterloo. I doubt it would even be connected in the London direction.
TUI - That little used freight line to the west of Heathrow is for an oil terminal. It connects to the Great Western main line in the wrong direction for Reading... not sure about the land around there, whether a third leg can be built making it into a triangular junction. You're right though, that's something they've been thinking about.
Last proposals I heard were that T5
would be a four-platform station - two for HEX
; two for Piccadilly tube. When/if the connection to the west opens, whether it be to Feltham or to the GWML, the station would be expanded to 6 platforms.