njakes
Depends on exactly what he is updating, Plasma / qt / frameworks / applications.
He has to update to the new source, rebasing any existing patches, potentially adding new patches, add or remove build / run dependencies that may have changed since the last release. compile / do safety rebuilds / package. A single package could take anywhere from a few minutes to hours to build. Once complete he can install and do some local testing.
Once he is happy he will push it to the build server in tiers. So if package-x depends on package-y he has to make sure package-y is in a lower tier (gets pushed first). The build server works by using a package.yml which is basically package build instructions. So the server will now compile EVERYTHING again. The server is often slower at this than many of our more higher end systems like my 3900X.
It is my understanding that he has automated some of the pushing to the server but he can not just walk away and trust it will do its job. He has to monitor it, things will often fail to compile for whatever reason and the script has no understanding of this, so it would keep pushing potentially resulting in a broken stack upgrade. So he has to babysit the build server.
Suffice to say when its a large update, Girt has no weekend. There are hundreds of packages involved.
Then it gets tested in the unstable repository all week. Team and community members help test. Some issues might be found in testing that would require him to research, patch, rebuild or revert.
I know I often go to sleep with girt pushing stuff to the build server, wake up 8 hours later an he is still going. Not fun.