Master of Stables is the leading branch marshal that oversees the administration of the Marshallate in the Canton. From the An Tir Admin webpage; Great Officers:

“A branch marshal oversees the administration of the Marshallate in the local group. Their special duties are: seeing that information is made available to all fighters on armor standards, conventions of combat, rules of the lists, and any other information they are directed to distribute; ensuring that the local branch has trained marshals present at events; ensuring that fighters and marshals in the local branch receive p roper training; supervising marshaling activities at events; assisting in the authorization of new fighters (this means giving local authorization, which is to be redone at kingdom lev el); and making sure that equipment conforms to the required minimums of the kingdom regulations as listed in the An Tir Book of Combat.”

Apologies, but no results were found for the requested archive. Perhaps searching will help find a related post.