Just having a look in Hot Stuff - as you do - and I see a Morris C9 Armoured Car is due for release sometime in 2010 and also a 18pdr as used by the BEF.
George Moore is/has designed them and I've had a peek at the 18pdr which looks cool as does the Morris.
The Morris will be a welcome addition to the range of Armoured Cars that are currently available, great to have some of the early guns and vehicles in the pipe line.
Al
