RAS Contracts and changes to the NPPR

Up until the budget last December properties rented to the councils under RAS agreements were exempt from the NPPR. This exemption was a major selling point to the councils and the exemption as stated on there web sites and information booklets etc.
Having agreed to sign up to long term agreements where this exemption as a major deciding factor i would be interested to know if anyone else in the same position and does anyone know if legally this can be done.
The agreements themselves do not mention the NPPR.

Also interested in the reply to this as I got the letter stating that we are now responsible for the charge.

I would think this issue exists completely outside your lease agreement with the relevant CC.
The exemption of the NPPR for RAS properties was initially brought in to encourage transition from the previous s/w payments which were always supposed to be short time/emergency accomodation to the more permanent RAS scheme,in light of the fall in rents etc the RAS scheme is oversubscribed now in a lot of CCs,therefore the exemption is no longer needed,a bit of a pain alright but nowt you can do about it I would think.