Shoutout to
@Fatih Ozcan for reporting this
A bunch of add-ons are using the 90-prefix to bump down the version_string, while still using a larger number.
We had code in the backend to handle this when parsing the version from add-on pages, but had forgotten to add logic that could automatically notice & mark these add-ons as using the "90-prefix/hack". So a couple add-ons in our system were being parsed as using "normal" versioning.
Because of this a couple of add-ons have not been reported as having updates when your forums' have checked in.
The backend is now fixed so that it can automatically mark add-ons using the 90-hack