Hi everyone! Welcome to Forums. Thanks for sharing your thoughts on this thread. It’s Juan here from Zwift.
As you have mentioned, because training plans are flexible and can be completed in any order, expiration date only reflect the last day of the current week. The “do by” message will be removed in a later version of Zwift. I’d like to suggest you check periodically this forum thread.
Regarding schedule to do them. The Companion app on your phone will show a list of upcoming workouts so you can see what’s in store. You can learn more about it Zwift companion app by clicking here.
On Zwift Companion you will have the ability to see the full week’s training plan, it helps you consistently complete your workouts.
I hope this information has been useful. If there is anything else we can help you with, please let us know. You are always more than welcome