The Poultry associations will not encourage new breeds because they'd be inundated with every home flock keeper insisting their "special hen" is a new breed, even before it's produced a single chick. If you fix the breed characteristics and present the new 'breed' with genetic info, lineage and records with photo proof of the breed characteristics breeding true through generations, you'd probably be considered seriously. You just need your proof lined up properly, instead of showing up with a chicken in hand going 'Look! It's a new breed!' which is what 99% of people do.

Like hatching out a slightly different baby BP, which would be a possible dinker... but instantly declaring it to be a new morph. To be taken seriously, you have to show it's a genetic trait.