December Bumble Bee

This unseasonably warm weather will have had a number of effects on wildlife. On December 17th 2014 at 13.30, when the temperature outside was 12°C, I spotted a bumble bee worker buzzing around the Mahonia flowers in my garden at Callow Hill. On closer inspection it had two full pollen baskets and as I watched it moved across to nectar on winter-flowering heather close by. Now is the nest that this worker is provisioning a continuation of the summer nest, or has a new Queen come out of hibernation early and started building a new nest already?