Might the Home::1 tariff help there as an alternative to jumping to another ISP, getting rid of the peak/off-peak split?
(I'm in the opposite boat right now - approaching the end of my year's FTTC commitment and thinking of jumping to A&A when I can. Last year, I could get FTTC but not Be ADSL, which on the tariffs at the time ruled out A&A; the arrival of Home::1 seems to make it viable for me.)