Strike 2 and still out
The backbone of the London Underground communications infrastructure was a project called CONNECT. It was let in about 1996 to be finished in 2003 and is still incomplete. Ir was to cover both the extended radio network required by the 1987 Kind Cross Recommendation and the need for a digital backbone to carry all its communications services until 2020-ish. It was another PFI which was subject to the usual massive changes in specification, and delays brought about by the inability to allow the contractors access to the sites to undertake work.
Note that the TETRA infrastructure system in the Underground is still incomplete on two major line (Northern and Central I believe), and does not support the police, fire and emergency services ubiquitously as envisaged.
No National Audit Office report has been carried out, as to why nearly 10 years after its original completion date, it still is not. The person who signed the contract at London Underground is not a Peer of the realm.
Personally I wouldn't waste my time wit them anymore - if they want to buy kit, fair enough but the minute they get into design, we are back to a customised design which ignores the already working systems elsewhere in the word. Thats one way to keep TfL staff in a job !