Your plan
My upcoming workouts changed on their own
Once, after an update, Why Not rebuilt the weeks ahead of you with more variety in the hard sessions. Your past runs, the current week and any week you changed by hand stayed as they were, and Home told you.
If you prefer the plan as it was: Settings, About, tap the version seven times, then Restore plan from before the workout update.
Settings, About, tap Version seven times, Restore plan from before the workout update.