This is not an official answer, but I’ve been successfully upgrading 8.0.x minor versions by just pulling the new code on top of the old one. Just unzip the files.
Make sure you have proper backups in case anything goes wrong.
Have you tried the upgrade guide (check link at the end)?
You need to:
Download the new version install zip package (the one from the suitecrm website, not from github)
Note: Suite 8 does not have upgrade specific packages. You can use the new version package as the install package. E.g. if you want to go from 8.0.0 to 8.0.3, you can use the 8.0.3 install package (SuiteCRM-8.0.3.zip) as the “upgrade package”.
Place the package on the tmp folder (see the guide for the correct place to place it)
Re-set permissions
Run ./bin/console suitecrm:app:upgrade -t "<version>" where <version> is the name of the package (whithout the zip) like SuiteCRM-8.0.3
That is, copy and paste, and that the system replaces the existing files and put the new ones?
And in the case of customizations, use the export option?
On SuiteCRM 8 you can use the package of the new version as the “upgrade package”.
For instance, if you want to go from 8.0.0 to 8.0.3 you can use the 8.0.3 install package as the “upgrade package” and place it on tmp folder (according to the instructions).
SuiteCRM 8 does not use a “delta” strategy like SuiteCRM 7, you use the full package and SuiteCRM 8 will update it self by using the files on the new package. It will “fully” override it self expect for some folders that can have customizations, like “custom”, “extensions”, etc