Been searching around on various 40k wikis as well the DH rulebooks and so far I havent been able locate any concrete sources on Adeptus Arbite recruitment other than the book of judgment stating they're progena groomed for the role. Just wondered if anyone can recall or even link material confirming other recruitment channels besides progena? Whether it be another official route established in the imperium or a novel in which a character is offered it for whatever reason.
This for me specifically concerns things such as the Chastener's various required careers, the idea of a mutant arbitrator (as subtle or useful as mutations may be I dont think they wouldn't picked up by or tolerated by mega stringent recruitment tests) and just generally the possibility of an arbitrator acolyte background to not be of progena stock or an acolyte earning/being offered the role throughout his adventures?
I know people could suggest passable backstories or eventual situations made up to cover these concerns however, I'm only interested in people replying with official material (or informing me there isn't any other) detailing non progena recruitment channels for the Adeptus Arbites.
Many Thanks, Ordo Neriman