Wouldn't this be just the thing the Emergency Update tool (scheduled task) should be used for ?
Actually no. avast! Emergency Update is designed to update avast! in case if avast! service itself fails to work because of some fault in the update.
For example if they released an update which turned out to cause horrible avast! problems where no avast! interface loads up (including tray icon), avast! service fails to run and updater fails to operate. In such cases avast! Emergency Update will still work because it's a standalone app being triggered by a Windows Task Scheduler.
I'm assuming this app works a bit different and they have some sort of server trigger. If this emergency updater detects it on their servers it will roll over the files and data found on the server, potentially recovering avast! to its operational state again.
What we have here is just a crash problem with one of its components, you still have avast! and internal updater working so a normal program update can be released. I also know they can enforce the program update if they want so that users get it right away if needed without weekly waiting to spread out the load on servers or to ask user for confirmation.