Yessssssss just managed to grab a bed at Motion Chueca for £48 on the 1st. I'd almost given up on refreshing booking.com but it paid off in the end.
Also, one I was looking into myself. Hostal Los Alpes have a bed listed on hostelworld for £30, but you can't book it as they have a minimum requirement of 2 nights booking on those dates, but the 31st and 2nd are fully booked. I contacted them directly about 20 minutes ago about booking the room some other way but obviously won't need to now. Might be worth looking into it for anyone still not with a room. Their email address is info@hostallosalpes.com