In some special cases, FirstOfficer did not book upgrades between annual plans right. Events were missing from the period between the proration and the new subscription start date.
The problem is now fixed and the metrics are being regenerated for the handful of you who were affected.
The current total of automated tests in FirstOfficer for catching special cases like this is 289, so hopefully we are approaching the point where most of the special events from Stripe are handled right.
Check out our best practice guide to using stripe API to learn more.