I wouldn't be breeding that snake for several years, if ever. I don't understand the rush, either...the world isn't running out of BPs.
I'm not a BP breeder & never was, but bred various other kinds of snakes. Health of the snake comes first, undersized snakes can have full-sized issues.
(and for what it's worth, I don't look to breed snakes under 4 years of age, & not every snake is well-suited to breed)