Hi Ro, Welcome to the forum!
Please could you clarify which events you’re talking about as I’m slightly confused?
I had an issue early in the tour where some stages weren’t appearing on the Zwift Companion app. If you’re not seeing the following, then it might be worth you updating the Companion app or logging into Zwift.com on a browser to see the events there.
The Tour de Zwift rides are every hour, 24 hours a day, 7 days a week.
The weekend-only Tour de Zwift races start at 00:30 on Saturdays in the UK (13:30 Saturday in NZ) with the last races starting at 23:30 on Sunday in the UK (12:30 Monday in NZ).