How do most companies handle upgrading if they have users with annual plans? eg. I sign up with olark bronze plan and 3 months in I want to upgrade to gold. Now what happens? Do you create a charge for the prorated difference remaining in year?
The issue comes in how you calculate your SaaS metrics, because the MRR/revenue upgrade is easy enough (prorated over the next 9 or 12 months in your example), but it's tricky when trying to calculate where you attribute the customer upgrade.