Hi Fredrik,
The GA status is given to OSes which are proved to be stable or based internal tests outcome. This status can be on the day of publishing or after being as a patch for sometime and then changed to GA. These can be considered when an upgrade is planned by customer on his own as a part of keeping up-to-date. Patch releases are mainly with fixes for issues in previous releases + any urgent feature support (For eg: TLSv1.3 implementation). These are normally recommended to customers when they faces issues which are fixed in this one. Do note that, terming as a "Patch" doesn't mean that it will skip our internal testing. It is just to say that the release is more concentrating on a fix or feature which can't wait for the next GA release in the branch. Once proven stable, it may get awarded with GA status.
Note: Irrespective of the status, customers should go through the release notes for respective SGOS to understand the changes it may bring to their setup