Training plans and schedules

I am trying to follow a training plan. I have tried 3 different plans and with the same problem.

If I enroll a plan on a Monday, the plan is sometimes available the same day. Sometimes not. Most days I do the workouts in the morning or during daytime as that fits my schedule best. So, some enrolls and cancels normally open the plan for the first workout. If not, I cruise around in Watopia and try the workout the next day

I can then follow the plan with let’s say 4-5 workouts that week and finish the last on Saturday. Then on Monday checking Zwift on my computer it says workout available in 3 hours. Nice, I can do a workout at 13:00, but why can’t decide when I should do the workout? Going to my training room at 13, open Zwift (Apple TV) the workout is available in 6 hours. WTF… Going back to my office computer and there it says the workout is available. This is where I normally have canceled again and switched plan or just doing the first week over again.
I have read the Training Plan FAQ, but can’t find out what the problem is. Support says it is what it is.
Is there something I can do to make this work?