I, too, am having an update problem. When I last updated (April 18) I encountered an error and now my pinhole is no longer using https.
This morning, I went to update to 6.1 and received an error message that my OSis no longer support. I'm running Buster is supported.
$ lsb_release -a
No LSB modules are available.
Distributor ID: Raspbian
Description: Raspbian GNU/Linux 10 (buster)
Release: 10
Codename: buster
I did an sudo apt -update hoping this might correct the OS error. No luck. I then followed the pinhole error message deleting the OS check and that didn't work either.
Another note: as I recall in the past, I would simply enter pinhole -up. Now, it's requiring me to sudo pinhole -up
I'm running a Pi Zero2 and it's been working flawlessly - until two weeks ago - for several years.
I'm a very casual linux user so I'm stumped on what options are next short of a total re-install which I'd really prefer not to do if possible!