Evidently it's been reported in Janes Defence Weekly that "M.O.D. sources" have revealed details of long term planning for UK operational Fighter/Attack squadrons. While no set figure has been agreed regarding F35s, it would seem that with the F35B entry into service, the R.A.F. will get an additional two Typhoon squadrons. From 2030, the expectation is that a number of F35As, or whatever development there of, which is available at the time, will over the following decade replace the Typhoon. By 2040, the R.A.F. will be flying F35B and F35A.
However, nothing will be agreed in terms of the eventual number of F35s of either version until SDSR 2015.
FB
