Anstey's is a year round venue, but does suffer from seepage. The empire of the sun wall is likely to be bad over the winter, with EOTS being the route affected the most. It will probably be OK at the moment.
The ferocity wall is a more reliable year round venue, and indeed late autumn/spring often gives the best conditions. The Cider Soak tends to seep more than the others, especially the big pocket on the crux but you can often get round this by filling it with a beer towel with the other end of your rope tied onto it (get your belayer to pull it out just before you do the move...). Ferocity wall will be fine at the mo