I have a JCB 300T that's never been in a heated shop. Starts well all winter. Display in upper RH side near key switch says something like warmup but has never been in that for more than a minute or two at the most on the coldest days. Engine doesn't fully warm up in that time on a cold day but the oil gets flowing around and the machine is useable in a couple minutes, usually just seconds. Cab heat may take a few minutes but machine is operable sooner.

I'd say there is something wrong with your machine, and you should get some warranty service. Yes Equipment in Madison is as good JCB dealer with mobile service.