Lighten up my friend.
Accept that whatever you are breeding aren't 100% pure..... When they start producing some serious notable honey crops and become more errhum manageable then perhaps people will start beating a path to your door.
Currently I have 2 nearly Amm queens generated from isolated matings, genome of their lineages puts them (by DNA analysis) at around 90-95% with some lingusta and carnica genes present (last I heard the Cornish bees were around 80%). Despite this introgression the nearly Amm's I have retain most of the characteristics described for the old English Black Bee small oval brood nest surrounded by stores and pollen, excellent white capping on their honey and black as the ace of spades. But I would never call them pure....whatever that means these days.
Down sides, chalkbrood in clubs!, And compared to equivalent sized colonies are poor at bringing in honey during a flow, My imported Carniolans and Buckfast wipe the floor with them in that aspect. Unlike little John the ones I have are excellent to work with, can't fault them on that. But I do hear from a few Cornish men that your "local" black bee has a bit of a reputation temper wise.
So please stop trying to pull the wool over peoples eyes. Honesty will do you and the local bee cause more good than harm. All we ever hear is hyperbole and little hard facts. We most certainly don't want the situation to develop into the Irish situation which, if rumors are true, involves shotguns and shooting hives of non local bees....
And all for a bee that only a dedicated few really want.
But if you would like some new "purer" bloodlines to introduce to your breeding program I shall happily donate the two queens I have to your cause.