The normal order of things is to prepare the pre-release/beta server for the release and then Vlk usually lets us know it is available and shortly after that it would become available in the auto update notification cycle.
For most people they don't wait for that but got get it using the manual update process. Some don't even wait for that but periodically check for pre-release refreshes so as to get it early

So this one is a little different if as Xmas said this is a regular release, then there are shed loads of update servers to prime for the release and then there is the auto update cycle to navigate as avast attempts to balance server load across its hundreds of servers and 100 million plus avast users.