are a charter operator they are not "low cost" as they still have things like inflight meals (they were free last time I flew them 2 yrs back) and Inflight entertainment etc. etc. they will be a low cost carrier in the same way that mytravel started mytravellite, or from recent experience mytravelsh*te
I was thinking that as Britannia are part of TUI along with HapagLloyd (who have HapagLloyd Express) that they may operate in a similar way to them i.e. 737-700, nice seats, IFE, low fares. But maybe not. Actually B738 most likely as they already have some of these.