On one level if Stirling University, Stranraer and Annan can have tier 6 teams last season, it's not obvious why the Old Firm shouldn't have them as well, until you consider the question of why they would want to be in a WoS league rather than the SPFL reserve league, which they are not currently participating in. Rangers don't seem to have been impressed with that setup and colt teams definitely seem to be the preferred way to go:
https://www.rangersnews.uk/news/rangers-pull-development-squad-out-of-spfl-reserve-league/
so Edinabear's info fits what is currently happening in many ways. If into leaks out of next month's PWG meeting the way it normally does, we should soon know more about what's happening.