[Lolzytripd]

Maintenance rank 3 no longer unlocks engineer

[Exxy]

I would assume the flag that comes from Maintenance is still drawing from the old source, since how he revamped/replaced to old system of Talents. Or it had flags relating to another portion of Maintenance (I would go with the first possibility I said).

[Autumn]

This would also apply to Priest unlock wouldn't it?

[Exxy]

Probably; I would say it's safe to assume so.

[Trexmaster]

I could still unlock priest in the beta, so I don't think so.

[Lolzytripd]

Priest is currently unlockable with staff mastery still

Engineer cannot be unlocked by any means

[Neus]

You should be able to unlock it still by winning a battle with a wrench equipped as your main weapon.