Tony, I fully understand your being anxious to have a Morgan as soon as possible, ......but....I have had a 4/4 and now have a plus4 - I have also driven the 3L roadster. I would have a roadster if it were not for the €2000 annual tax here in Ireland!!
If you can afford a Roadster I, for one, would suggest you have a cold bath and think... Could you live with the relatively modest performance of a 4/4 -- I am happy with my plus4, but find it a real step forward from the 4/4. The Roadster is in a different league altogether.
I fear the dealer may be trying to "conveniently" use up the build slot he is committed to, rather than having that car in his showroom unsold with another order for a roadster on hands!!!
I would advise you wait for the roadster - so long as your finances allow!!!