While I accept your ruling, I'm just posting this to show what I found and why I asked the question.
On p.129 of Street Grimoire, left column, 1st paragraph under the chart "For each member there is specific set of individual strictures that the group can establish if the group bond includes an oath."
And p. 142 of Street Grimoire, the Oath Ordeal itself. "The oath ordeal, in which the character swears an oath to obey a given magical group’s rules and strictures,"
I perfectly willing to go as is (the Ash Union didn't exist when my mage initiated), but you may want to address this officially because there will be players that say because there is no Oath ordeal, there's no way for a group to enforce the strictures.