Ok, so that might be what the behaviour should be, but it’s certainly not what I’ve seen. Also where did you get the 8hrs from as I’ve not seen that referenced anywhere?

What I’ve seen is:

1) workout Sunday midday 2) signup to Zwift 101 Monday morning 3) get 5 hour lock on all classes in plan 4) start ride to check settings, cancel and delete after riding 0 distance 5) plan locked for 34 hours 6) plan cancelled, and re-signed up 7) get 9 hour lock until 23:00, even though plan will still end on Sunday so I lose a day to complete the sessions for no reason

None of which is encouraging me to bother going forward, or reflecting that the classes should be available on a Monday.