In the case of v1.65.0, this hasn't happened, so the GitHub repo still has the unsigned one!

I don't understand. When I hover over uBlock0_1.65.0.firefox.signed.xpi link, it's the AMO's link:

Clicking on it automatically installs signed one.

The GitHub-hosted builds are always located under assets! :)

I don't ever remember the links under Assets being changed to AMO's links, back at even version 1.40.0: https://github.com/gorhill/uBlock/releases/tag/1.40.0

Only the link at the changelog section is automatically changed to AMO's link.

The Assets section never features AMO-links.
I was talking about the process of replacing the temporary unsigned uBO Firefox build with the signed version!
The process is either automated (and then possibly broken), or still manual (and gorhill has simply forgotten about it).

I just received an email from Mozilla that review was cleared at 5h41 this morning. Should I link emails from Mozilla to my alarm clock so that I upload it asap within seconds before someone commands me to upload it now?