I think it might be a good idea to allow admins the ability to auto-promote people from one group to another by date.

For example, new registrations are placed in "Group A". The admin can specify that after "x" days those members may be automatically promoted to "Group B". Or be able to combine the 2, so that the member in "Group A" must have "n" posts as well as be registered for "x" days.

This would allow for automated promotion without worry about members spamming posts to get promoted to the new group faster.

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