It looks like pip3 doesn’t consider a “post2” build to be a higher version number than a “post1” build: attempting to run “
sudo -H pip3 install panda3d” with the “post1” build already installed produces the following message:
Requirement already satisfied: panda3d in /usr/local/lib/python3.6/dist-packages”
Uninstalling Panda and then re-installing does, however, seem to then grab the “post2” build.
I don’t know whether I was updating incorrectly (I still don’t quite have the hang of pip, in all fairness), or, if this is an issue, whether there’s some other way of marking post<n> builds so that pip recognises them as updates. (Or even whether it’s something worth fixing.)
Still, I wanted to bring it to attention, in case it is indeed both fixable and worth fixing.