I only just noticed that "Winder123" (3 Oct 2015) seems to be describing something else that has eased "creaking". Missed this before because it's part of the "stamp on the footbrake" idea that seemed to be the solution to a different
problem to mine (but who knows ?).
In fact I had come back to this forum today because yesterday I used the handbrake whilst moving (not viciously, just losing the last few m.p.h. as I came to a junction).
And now my handbrake action is smoother again !.
Perhaps with their image of a "sporty" brand SEAT are actually expecting us to do "handbrake turns" ?
Seriously, I feel I have to mention this to my contact at SEAT customer services, as it
should be useful information to them (if they are actually looking at the
problem).