Well since you ask...
I was astonished and so was the mechanic at Halfords (who has looked after my three Boardman bikes over many years) because the bike is less than a year old.
It appeared that a lot of water had got into the hub (although I only ride it on tarmac and don't go out in the rain) and having stopped using it 5 weeks ago it had started rusting to the extent that it needed a real clout on his chain whip to disengage the cassette.
Anyway it is still under warrantee and he is ordering new bits so hey!
And may I say: Halfords may not be very fashionable and they don't sell Pinarello but I have had excellent service for 10 or so years from my local branch and even though I have Wheelbase on my door step I reward good service with loyalty.