How can I restore Calendar settings from a Time Machine backup (not iCloud)

I did that... and Apple couldn't help. I spoke to two different support specialists at two different times and neither had any idea of how to fix the issue.

In the end I worked it out for myself. I had to do a complete Time Machine restore of my iMac to before the update to Ventura (where, to my relief, all my Calendar info was present), then I went into Calendar > File > Export >Calendar Archive... and saved the resulting .icbu file to an external hard drive.

I then did a second complete Time Machine restore, this time to the iMac's post-Ventura update (present-day status), went to Calendar > File > Import... and imported the .icbu file from the external drive. Hey presto, all my calendar data was restored.

It did seem to be a rather needlessly long way round for what should have been a simple restore job, but I got there in the end.

Do I get a prize for being a better tech support for this issue than Apple and the communities? ;-)

I opened Macintosh/Users/username/Library/Calendars (the folder which holds the .ics data) on my iMac, then opened Browse Time Machine backups in the menu bar and chose a date before I updated to Ventura, which took me to the same folder from that date on the backup.

I hit Restore, then Replace. Once that had completed, I restarted my iMac, opened Calendar... and now have a blank calendar.

This is a real problem, because I rely on my Calendar data for my business. I back up regularly, so not being able to restore the data that updating to Ventura corrupted is really frustrating.

There has to be a way of restoring all my Calendar events?

An old thread reveals that it seems this is not a new issue. This is what I tried and hasn't worked.

how to recover calendar from time machine… - Apple Community