Its not BT/Openreach that are the problem - all the ISP's will have the same information about your FTTP line.
However, most ISP's have chosen not to support FTTP lines at the moment - including the big non-BT players like Sky and Talktalk - and this is why they are telling you their services are not available.
Some of the ISP's who do support FTTP are (in no particular order):
1: Andrews & Arnold Ltd
2: Zen
3: BT
4. Plusnet
5. IDNet
BT also offer Infinity 1 on an unlimited data tariff which might suit you if you are happy with the speed otherwise.