They fell out with bell and colvill, and they were like an ambassador for the brand, one of the highest regarded Lotus specialist in the country. You would think Lotus would have tried more to keep them on side. I don't know the exact reasons for the Lotus/Dealer 'issues' but I suspect selling cars direct from the factory bypassing dealers, and making warranty claims slow and painful for dealers are probably top of the list..
For Auto100 I've noticed they always have around 10 cars listed on Autotrader at any one time. When one sells another pops up in it's place. I don't know if they have a large inventory and only list a selection, or if they have some arrangement with Lotus to keep supplying them. We'll probably never know as they strip the history and paper trails from the cars. If you ask Auto100 (and I have) they tell you they're all ex Lotus management cars. Well they sure have a lot of managers driving around in Emira's!