If you select "reschedule" in a workout, the workout disappears completely from the plan, and a rest day is added to every day of the plan.
The training plan becomes unusable from this point on.
Support is already aware of this known issue. Check out the related thread for more details.
I didnt wait for them to come back. I deleted the training plan last week, and added a new one. Since my event is in 4 weeks, and the training plan is 6 weeks long, It is now offset in my calendar so I have to look at the workout two weeks in the future to know what Im doing today :/
If you are experiencing this please refer to the following thread for updates: RE: garmin coach re-schedule activity and it disappeared.