We were in Rodellar in late Oct and it was seeping due to some huge rains the week before, but I know of people getting great conditions in Nov/Dec, but it can be pretty cold. It's pot luck really, but there is still lots to do that doesn't seep even if you don't get lucky. Sector Egocentrisimo and the arches at Ventanos are both pretty seep proof and really good, plus the warm up crag is always fine.
The other place you are thinking of is Alquezar (pronounced Al-ke-tha). Less than 30minutes drive away. Alquezar is a very beautiful village which is a lot bigger with more facilities than Rodellar. The crags are behind the village. This is one of the main sectors, which has some superb long vertical type stuff on perfect rock, but can get too hot midday (you might be ok in Dec).
Same crag. Climber visible for scale. Thare is a world class 6c+ tufa line (route 15 on second topo) just out of shot on the left with a 7b+ extension (40m in total).
This is the other main section. The caves visible down the valley on the left are HUUUGE and home to some mind bending stamina fest.
Topos
http://www.climbermania.com/croquis/alquezar_cuevas.pdfhttp://www.climbermania.com/croquis/alquezar_lacolegiata.pdf