Bookings availability latency produces incorrect booking details

When a bookings page is first loaded, all days show up as available. If I quickly click on a time and then a day that should be unavailable and then "Next", then Bookings will produce an inconsistent result - the confirmation page will display the day I clicked, but the calendar invitation will be for the original day.

In this example, when the page loads it selects Monday December 2 by default. If I click on a time slot (2:45 PM) and then on another day (Saturday December 7) and then "Next", it will proceed with the booking as normal for Saturday. However, the actual invitation is for Monday. Is this a known issue?

I am doing this with my own private personal booking, using a link from the tile. This works when logged in as myself (i.e. opening another tab) and when proceeding as a guest (i.e. opening an InPrivate window).