Charge Full Amount on Upgrade
When a user upgrades it should charge (or at least admin option) the Full Amount of the new Product/Tier minus the current product unused amount.
This forum topic talks about this as well:
- $100 - 100mb
If user upgrades to product B on the last day of monthly cycle.
They "amount due today" would only be $3.61
We need the "amount due today" to be $98.30
We don't want to allow access to the new tier without paying for
the full amount of the new tier.
In more detail:
1. An an option so that if a user upgrades it can charge a full cycle amount on the new package and set next due date to 1 cycle from today
2. And oppositely if a user downgrades, then just credit the difference back and keep the next due date the same.