Four Horsemen crash at 66.0km (twice)

I’ve attempted the Four Horsemen route twice now and on both occasions Zwift has crashed, seemingly at the exact same location, 66.0km into the ride. This was disappointing the first time but infuriating the second time it happened.
First occurrence was 4 July 2020, I think it was a group ride starting at 09:00 British Summer Time.
Second occurrence was 5 September 2020, this was a race starting at 09:30 British Summer Time.

I’m using a Windows 10 laptop on the latest version of Zwift (I updated this morning and usually update each week) also using Zwift Companion on Android (Oxygen).

Is this a known issue?
Could you please look into this and resolve it?