The program does not update itself. It stays on the version the setup installed until a new setup replaces it.
What that means for you
You do not have to do anything. No update prompts, no “restart to finish installing” while a service is starting.
A new version arrives with a new setup. Nothing changes between last week and this week unless somebody decided it should.
Your own OBS is unaffected and can keep updating as it likes; it is a different installation entirely.
Checking which one you have
Settings → Info → Engine. Quote that together with the program version when reporting a problem: those two together identify the combination you are running.
When it does change
Running a newer setup replaces the program but leaves the configuration folder alone, so your settings, scenes and designs survive.
A second run of the same setup is quick: there is nothing to replace.