I think it would be useful if the workout available time was more specific, my workout said available Wednesday morning, so I got up early before work to complete the ride and then found out it wasn’t available for 3 hours…I’m sorry but for most users this means not available until after work. Part of following a training plan is the planning life outside of zwift and inaccurate information makes this hard.
Try changing the date and / or time on your device then change it back when you are in the game. If running Apple TV you can only change the time zone.