Second, I'm not actually that sure that there's a genuine need for April queens
I used one to replace a drone layer at the end of March but an alternative would be to combine with another colony.

Totally agree with the need to organise breeding programmes.
If I were to sell AMM queens to beginners in Devon it would wreck the open mating of the people who concentrate on Buckfast.
I suspect the main demand for early queens is from companies like Easy bee who bring in Carnica queens from Slovenia to make up nucs asap for new beekeepers who are not even aware of the issues surrounding bee breeding and imports.
Some of these were being ordered by beginners in varroa free zones in Scotland - completely unaware of the implications of that.
In general, the established beekeepers are selling nucs rather than buying them.

The thing is, all the commercial guys use the lack of early local queens to justify imports so for that reason alone it would be good to have queens available to render that argument redundant.