perhaps a visit to the
Citizens Advice Beaureau ...

or just say "It was your balls up and I'm skint. I can only afford to pay it back at 10 quid a month".
(haberman is singing in the changes, Thu 22 Jan 2009, 13:40, 1 reply)

In all fairness
to the incompetent fuckers, they have said that we don't have to pay them 2 grand for 3 years worth...they have been ever so kind and only charged me for last years, but even so, it means I am now paying an extra £80 a month on current gas and back pay for last year....

Oh well...it was nice while it lasted!
(iwantmybed Is counting down the hours till home time on, Thu 22 Jan 2009, 13:54, closed)

they are not being nice
It's their legal maximum claim against you:

www.legalbeagles.info/forums/showthread.php?t=1576

In a nutshell: you don't have to pay anything beyond 1 year of backdated payments if it's their fuckup.
( chart cat has an itch, Fri 23 Jan 2009, 5:55, closed)