Hack to change member group after certain time period

[magna]

There are many forums that offer a priemium or paid for section. I have looked and looked to see if there is a hack to automaticly change that member back to normal status after a certain time period.

Lets say they pay for 3 months access to a prefered section, is there any way to make a hack to automatically pm or email say 5 days before there prefered status is to run out and then have then automatically revert to a specific group or the group they were previously at.

Hope that makes sense, but I know there are many forums that would benifit by a mod like this.

Thanks