Thunderbird and Google Calendar issues

I run Thunderbird on both my desktop and laptop, accessing a mix of POP3 and IMAP accounts.
I also have Lightning (ver 3.3.1) and Provider for Google Calendar (ver 1.0.3) installed.
Both systems are now OS 13.2/KDE, although my issues began earlier in the fall, while I was 13.1/KDE.

I normally connect to and display 2 Google Calerdars, one is my own account(CAL1, access RW) and one is my daughters (CAL2, access RO).

For some time now, I have had difficulty gettig CAL2 to display. After looking around today, I suspect is has to do with the retirement of a Google API on Nov 17, 2014 (found that on the Google Provider info page), but I am fairly certain my issues started a month or so earlier than that.

With upgrades to both my desktop and Laptp this week to OS 13.2, I now am running Thunderbird 31.2.0
On starting up 13.2 for the first time, on both system (separated by 3 days), I was forced to re-enter login and password for both Google Accoiunts , acknowledge a boilerplate page and both calendars were available on my Calendar Tab.

But I find that with both systems, a reboot OR a sleep-wake cycle causes the CAL2 to no longer display. Stopping and then restarting Thunderbird has no effect. I am Not prompted to login to either the CAL1 or CAL2 accounts, CAL1 continues to function OK but CAL2 does not display.
Looking around a bit on the Provider for Google Calendar webs, appears there are several folks having issues.

Obviously (I think) this is an issue between Mozilla and Google, but I thought I would start here and see if others are experiencing this and, perhaps, have resolved the problem.

Thanks

OK, for now I am back in business.

What I did: Found THIS guide.
I deleted the problematic calendar, I enabled debugging for calendars and then walked thru
“Accessing Your Calendar” and added the calendar back into my Thunderbird setup…
It appeared properly and has survived two Thunderbird shutdowns/restarts.

Starting thunderbird from the CLI displays a lot of calendar interaction messaging.
None of that messaging revealed an error prior to removing then re-adding, but I could have missed something.

So far, I can’t find anything that was ‘wrong’ in the configuration (View-About-Config), but a manual scan there is difficult.

Problem fixed (for now), can’t pinpoint root cause.