Send later completely ceased to check?

[benr-cogapp]

A while back Send Later, AFAICT, ceased to 'check'.
That is, the UI works, and messages that I 'send later' appear in the Drafts folder with an appropriate date and time in the 'Send Later' column. But they never send; and the expected "PEND" message never appears in the status bar.
Unfortunately this has happened when I was busy and moving house, and I cannot now recall whether it coincided with a change from an old Intel Mac laptop to an Apple Silicon one, or a change of macOS, or a change in Thunderbird version. The problem has certainly persisted through a couple of Thunderbird updates.

I've tried changing the 'check every' (checkTimePref) setting; the changed setting is saved, but it makes no difference to the problem.

I'm currently running Send Later 9.2.7 on Thunderbird 102.7.1 (64-bit) on macOS Monterey 12.6 on Apple M1 Pro chip.

Evidently Send Later is still working normally for a lot of people, so I'm guessing this isn't a very generic known issue.

I've also changed the logConsoleLevel setting to Debug - but I'm not sure where I'd look to find the log messages.

Any suggestion of what might cause this, or how I can investigate further?

[benr-cogapp]

My apologies - I don't know why I didn't see it before, but this is in fact the same issue as #500. Following advice in that thread I've uninstalled 9.2.7, installed 9.0.11, and it's now working as expected.