Leigh, effectively I had a brood nest that bridged between the original BB and the 14x12. I demarried to hatch the remaining brood and took some queen cells from the demarrie as well and planned to use the drawn comb for nuc's etc. The colony was so strong though that I dropped that idea and ended up giving them back the Nat BB later in the year and then left them on it, hence the 2.5 Brood colony I now have and hope to winter in that format as a trial. My thinking is that on an OMF you often put a super under to protect againsst drafts so the only diff here is that they have some comb and stores and can hopefully start low and move up, they also have a big winter population but of course much more stores into the bargain. At this stage there are still 5 14x12 frames of brood, the bottom of the brood nest is half filling 4 of the std nat frames below and they have loads of capped stores. Should be interesting - Have now taken 12 ltrs 2:1 in a week and are pigging out on ivy and HB. The straight 14x12 colonies have visibly less traffic by a long way. It could of course all goes mamories-up but we'll see and I have 3 other strong hives wintering, so there is insurance.
and all of mine are local mongrels, this is yorkshire remember, I've heard that some people down south pay good money for bees?