Just had an email from PPHE (Park Plaza Europe) with information on their January Sale, including London from £89.
Link here:
http://www.parkplaza.com/january-sal....offer.booknow
Book by 7th January for stays until 12th April.
Might come in handy for some, though of course always compare to the 241 rate if you qualify, as there's a good chance that might be better value anyway.