I have upgraded to Mojave beta 5 and my calendars no longer sync with my iPhone X running iOS 11.4.
Do I need to upgrage my iPhone to iOS 12 beat as well to get the calendars to work?
Thanks.
syncing calendars with Mojave
Had various issues with this in Beta 4 - Apple could not help. Had to continue to try different solutions. If you have more than one Apple ID this may be a problem. In the end I had to reinvite everyone on my shared calendar list, and change to a different Apple ID that I have used for my MacBook Pro... whilst still using the same Apple ID that I always had been logged into Calender. I believe the whole thing was iCloud related.