Hi Former Member, I had the same question and came across your post. I think to have found in the meantime a workaround:
I missed yesterday's training and want to catch up today. I edited my training schedule…
This doesn’t work, as it only display future workouts. Not the ones in the past (I.e. yesterday).
Benchmark run is different. It’ll still be there as technically the coach training plan hasn’t started yet - once it’s started, rescheduling option for missed workouts doesn’t seem to be available.…
So I called Support and they were stumped! After reading many threads, what someone said below works!
1. Go to Garmin Connect on the web
2. Select Calendar and open it
3. Drag your missed workout to the day you want to make it up
4. BAM!! Resync the watch and you will see it!
The adaptive Garmin Coach programs will adapt. The "regular" fixed programs won't, to my knowledge. The Garmin Coach programs probably adapt even better if you also move your program end date forward by two weeks (to make space for the adaptation).