Different Ignition Versions using Git

If you update Ignition from a minor version to a newer minor version upgrade and are using git between dev and prod and prod does not get upgraded, can you still push updates to prod using Git?

Or since they're different versions, this will not work properly?

Dev on 8.1.23
Prod on 8.1.18

You cannot safely move arbitrary resources between versions backward. That would imply 'forward-compatibility' on prod, in this instance, which is not something we even attempt to maintain.

Dev should always be exactly the same version as production. Except the brief period where you are preparing to upgrade production, and the upgrade process is the only thing you are testing in Dev. If you are an integrator, you should be using separate VMs for each client, set up identically.