If it's a PN Hub One, then logging in will give you your current firmware version at the bottom of any page.
Some users have reported 18.104.22.168.22.214.171.124.2
Most would be on 126.96.36.199.83.8.259 (though this introduced a wifi issue for certain devices
And 188.8.131.52.83.8.263 is a manual process atm, probably moving to auto anytime soon(ish)
If you're on the middle, then PN can push it to you if you report wifi issues.