I think this may have to do with urllib library in use. If doing a third check for add-on updates succeeds, then yes, it is a temporary connection
Only after restarting NVDA.
At the moment I have suspended add-on development except for major and critical issues in order to concentrate on highest of highest of priority work in NVDA (Python 3).
Well this is certainly not that, I just wanted to point it out as a potential thing to know about. It's probably a corner case anyway.
