Basically, a subscriber is on plan $60 for six months
After 2 months subscriber wants more benefits/access, so wants to upgrade to $120 for 6 months. Essentially at this stage, they have consumed $20 worth of the $60 subscription.
Can the subscriber "upgrade" to the $120 plan?
Is the action simply that they start a new subscription for $120 for 6 months
..... can they somehow get a pro-rata credit of $40 automatically applied?
If not, they'd end up paying $180 for 8 months .... where if calculated it should only be $140 (the 120+20)
Just wondering how this is handled with latest releases and functionality.
Thanks heaps, Max