Reviewed this thread so far but have not found mention if the auto-updater (well, to be correct, the scheduled updater) PROMPTS the user before committing any changes. Yeah, it might be handy to have it check for catastrophic fixes to Avast (and why this separate process is needed to download AND RUN the fix program) but I don't want something making major changes to the state of my host without my permission. Microsoft can wail all they want about what are critical or important Windows updates but I configured the AU service to prompt me for my permission to download and install the updates. I'll choose if and when to apply changes to my host - just like I make that same choice of what software I install on my host.
They don't even notify me that they added the scheduled event. As a consequence, they don't let me decide when the scheduled task runs on my host. Only after accidentally finding out about the new scheduled event can I then know I have to reschedule it. They simply toss in a time for the daily event based on whenever I installed the program update that added this scheduled event. Sorry, but my computer has other tasks scheduled at that time that will not get interrupted because a non-critical application (which includes all security software) wants to perform some catastrophic repair of itself. So not only does Avast surreptitiously add a scheduled event but it can interfere with other scheduled events. They behave like they have blinders that see only their product without any thought that users may already have a list of scheduled events and which are scheduled to not interfere or overlap with each other.
I've noticed some users note that the scheduled emergency update downloads a file. That would be pointless. It would download AND RUN the downloaded file. So the emergency updater, a scheduled task, upon discovering there is a fix file to download, should first prompt me if I want to download and apply that fix. If I have more important real work to accomplish using my host, I'm certainly not going to let some security software alter my host and probably require a reboot to interrupt my work. Consider how rude it would be for a program to patch your software (OS or apps) and then reboot the host without ever warning you and without ever asking for your permission. Bang, your host just rebooted in the middle of your work and your document or work just got discarded. Well, not prompting me to allow the update in the first place is just as rude.
For now, I'm disabling the Avast emergency update scheduled task because there is no good information from Avast about it. They didn't bother to describe it to me, they don't describe its operation or behaviors, and they never mention if I get prompted to then decide whether or not to permission the change. Yeah, it's there software but it still remains MY computer!