To be re-instated they'd have to have been considered nobility in the first place, or even accepted as a member of bloodline which in most cases these were bastard children or children of denounced lines in which case is being a commoner. You were denied in name, and continued to be until you were of both use and proven to be of a bloodline even today there are common people who if were to research their ancestral lines could petition for recognition of a noble line. The Tudor line it self produced so many bastards it's predicted some still exist though the royal line is considered dead.
Adventurers are considered to fall into this category, and yet they are still commoners, a commoner with possible claim but commoner nonetheless.
Once an adventurer has acquired three recommendations and become a noble,
they were always a noble and their nobility was simply recognized.
Before an adventurer has done this,
they are nothing but a commoner and can never become a noble.
You have to be able to apply doublethink if you want to understand it. Medieval logic is not like modern logic.
(And no, this is not tongue-in-cheek; this is essentially the official RP explanation for the situation.)
