I would like to add some personal thoughts:
While i think it is important to be consistent along all files of a same type, i see no real benefit in adding the stud type in title as well as keyword tag, since the file name 3626a/3626b/3626c does already imply the stud. To enforce it as text is some kind of information redundancy and adds, as this specific case shows, another possible source for errors.
An end-user who searches the pattern will possibly ignore the stud type, as it is of very low importance. And people who really want the correct stud type for their models will probably know what they search for (a/b/c variant).
While i think it is important to be consistent along all files of a same type, i see no real benefit in adding the stud type in title as well as keyword tag, since the file name 3626a/3626b/3626c does already imply the stud. To enforce it as text is some kind of information redundancy and adds, as this specific case shows, another possible source for errors.
An end-user who searches the pattern will possibly ignore the stud type, as it is of very low importance. And people who really want the correct stud type for their models will probably know what they search for (a/b/c variant).