How do I remove from group after x days

[BenCurry]

Hi, 

I want to use Secondary group promotion to offer a product discount.  

User buys an event ticket so is promoted to a group (ATTENDEES)

ATTEDNDEES get a discount on the next event if they buy the next ticket inside x days of the last event finishing. 

All of the above I have working just fine.  

How do I demote users from ATTENDEES group after x days?  

I looked in the Group Promotion Rules and i'm not sure if its possible?  Can anyone help with this? 

Thanks. 

 

[opentype]

I doubt it will work with group promotions. You can’t make the time passed after purchase a trigger. 
A Commerce subscription could do an automatic demotion, but that also might not work for you, since then you have subscriptions, not just one-time event sales.