However, a new install will always have the same schema version as the product version. So a clean install of 1.29.0 will always show a schema version of 1.29.0.

This does not necessary mean there is a migration for 1.29.0. The correct way to know which versions have a schema migration is to extract the contents of the database-schema zip. It will also be noted on the release notes.

Yes.

To ensure compatibility, I would recommend keeping your client library in sync with the version of FusionAuth.

For example, if you have 1.21.0 installed, that would mean ensuring you use the 1.21.0 version of the Python client.

Officially we don’t require anyone to upgrade. However, generally speaking we don’t back port patches, this means if you need a fix you’ll have to upgrade to get it. There are a lot of good reasons to keep a security product up to date.

But when you pay for an edition of FusionAuth that includes support, you can run whatever version you want (more or less).