This is not a feature integrated with s2Member per say, but there is a small third party hack you can purchase (sorry, it is not free), that can do exactly that:
http://krumch.com/2012/11/06/kc-s2member-ccap-drip-timer/?ap_id=Cassel
(this is an affiliate link for tracking purposes; I am not getting any compensation for it)
That hack allows you to drip content based on the purchase date, and not the registration date (which might differ). Also, you CAN drip multiple classes simultaneously, even if they didn’t start at the same time, or have the same dripping schedule (although you can only have one recurring payment). I am using that hack and I can code something like this:
[s2If kc_drip_element(17_weeks) AND !kc_drip_element(18_weeks)]
Show content for week 17
[/s2If]
In my case, it will display the content for one week only, but you can use the time period you choose.
