I'll join you in speculating

since this thread looks abandoned, which is ok:
1. After learning of the existence of the AvastEmUpdate.ini file in this thread, I caught it, but just once.
2. On my box, it ran. One of the firewall logs showed that the process was created. Twice, once for each of those files in \temp. And another log, not posted, showed travels to several avast servers.
3. My understanding has been all along that two emergency updates might occur in a day. Hence this thread, when I saw more. By now I think I know it was streaming updates, relly.