It is good you are wary of keeping the same version of the Spine editor, especially near a release. You can set a specific editor version to do that:
Settings - Spine User Guide: Version
The version of the Spine launcher is different. Any Spine launcher can always run all previous versions of the Spine editor. Usually when we update the launcher, it improves things but is optional. Occasionally we do an editor release that requires new functionality in the Spine launcher. When that happens the reinstall dialog is different
it only asks you to reinstall if you try to run the latest editor version, and it lets you choose an old editor version if you don't want to update the launcher at that time. This latest launcher update is different
it is mandatory because if you don't update then your old launcher has a bug (a certificate expiration) and will not be able to reach the server after February 15, 2020. That's not good because the only error you'd see is "the server cannot be reached". This is the first time we've ever had to do a mandatory launcher update, and hopefully the last time!
