I've left my first two heaps/cages to do what they can until spring. They've been pretty much frozen since mid-December, though I know "stuff" goes on deep down inside.
My granddaughter has had two pygmy goats for about 6 months now, and they've brought me probably 80 gallons (300+ litres) of manure/hay which, with my own contributions, has got those bins filled to overflowing. Started a new bin in a sunnier place to see if I can coax more activity out of the microbes.
Inside the house the worms are reproducing happily and creating nice worm casting compost.
Life goes on, yea even in the depths of winter.