The BBMF I think has stagnated
Well it's only going to get worse LOL, it's not exactly a growing market is it, there are only so few British types we operated during the war and only a finite amount of those airworthy, as for Stagnation, well they added a DAK and a couple of Chippies which are display aircraft in their own right, as well as useful trainers / hacks.
As said the Mossie has not been done to a recognised approval, hence why it couldn't do its delivery via here in its way to the USA.
Wasn't there originally plans i read somewhere for the BBMF to have been gifted the BAe Mossie before its tragic loss? It wasn't far from coming to fruition at the time.