change primary user group on paid subscription cancallation
 

Hello,
I use paid subscription to change primary user group.
also, I use promotions to change primary user groups based on registration days.

cancellation of paid subscription set primary user group back to original only if no other change took place since the subscription began.

how can I mod the code so when paid subscription is canceled the primary user group will be set back to the original one or at least to 'canceled'?

will it be set back when the cancellation take place or when the current subscription ends? (ie if subscription is monthly, will user lose access in mid month?)

thx

anyone care to help?