Automatic group assignment & changing

[truckworks]

I've posted a few other topics trying to figure this out, but have been told it basically isn't possible currently. 
 
I've got a completely paid-only site, but we want people to be able to use it for 3 weeks at no cost.  Once that three weeks is up, they basically get all their permissions stripped except the basic welcome/help category. 
 
There is no way to automatically funnel people into that 3-week trial group, I have to manually place them in a 3 week paid subscription group and then monitor when their time comes to an end. 

[Suki]

Well, this certainly isn't core material but mod material.

I assume the people you want to have that 3 weeks period are newly registered members no? if thats the case, then a mod to change their membergroup on register can be done.

For the 3 week period, a scheduled task can be applied, when the task is executed, fetch whoever registered exactly 3 weeks ago and change their membergroup to another one with zero permissions. The task will be executed daily.

[margarett]

Suki:
http://www.simplemachines.org/community/index.php?topic=528889.0

And
http://www.simplemachines.org/community/index.php?topic=308635.msg3753796#msg3753796

I already outlined the same solution for the 3-weeks period I think that it only requires someone willing to code it