Not sure where you’re getting your info from @Mattphew but in the U.K. the supported banks are Danske and Starling, both offering Mastercards.
Not exactly high street names, granted but Starling isn’t trying to be, as it is a mobile only bank, but it is a U.K. one, headquartered in London.
As to when the “main names” come on board, your guess is as good as mine. If you want them to support Fitbit, your best bet is to contact them yourself.
