I only started using Avast (premier) 10 days ago on a Windows 10 1903 laptop, but had noticed (and read in these forums about) the bug with the Firewall set new network profile problem (it is only ever connected to my home network), with that dialogue showing up after every re-start ... and sometimes, but not always, after waking up from sleep. I was hoping the next update would fix it.
For me, it did open the dialogue after the re-start following the Avast update last night; but I've just done a second re-start, and this time no dialogue and the profile is still correctly set to private. So looking good.