This is one key detail I have mentioned before. I love the unknown nature of this, and it is just like doing fast group rides and races. The challenge (and fear?) of the unknown is a great thing to add to our training, IMHO.
It parallels my other comment about the aspect of doing interval training and counting the seconds to completion. I started doing some intervals “blind” and hiding the clock. I use it as a similar challenge to the Zwift races, in that I don’t want to know exactly when it will get easy. I think this mental aspect can be a great addition to the training we do.
I know I did a bunch of training and thought I was super prepared by focusing around 80% of my training inside a few seasons ago. I went into a race with great fitness, but mentally, I hadn’t challenged myself in the ways of group tactics. Result? I blew up on something I should have handled, but had too much self-doubt and questioned when the group wold relent. They did, about 5 seconds after I gave up, and I was out of the race.
Since then, I look for ways to test my mental strength along with the physical training. I think we have the opportunity through unknown intervals and racing on Zwift to include these “tests” that can help us prepare for racing beyond the physical.