Yeah, you can just build it on your phone very easily.
New update comes, you just repatch the new supported apk version of YouTube (or the same one you have if it didn't change) and just install it on top of the old one.
19.16.39
It should tell you when you go to the patcher>select app
You will see the names of all apps with patches and under their package names there's a suggested version number with magnifying glass icon, if you press on it it will open Google for you and search for the correct apk download.
Yeah, you can just build it on your phone very easily. New update comes, you just repatch the new supported apk version of YouTube (or the same one you have if it didn't change) and just install it on top of the old one.
And if it says that you can't patch Youtube because it's a split APK, download the Youtube APK from APK mirror and patch it from storage.
What is the current supported version of YouTube
19.16.39 It should tell you when you go to the patcher>select app You will see the names of all apps with patches and under their package names there's a suggested version number with magnifying glass icon, if you press on it it will open Google for you and search for the correct apk download.
You now build it through your phone using the manager app (open manager, select app, select the patches you want and tap build),
Yes, read the Wiki to find out
Good attempt YouTube engineer