I have training plans (source from trrainingpeaks) in the Gamin Connect app and site. I set up Edge 1040 Solar in the official way, meaning pairing it with my iphone and syncing with Garmin Connect app. The training plan was synchronized as expected and show up on the home screen and in the training plan screen.
I switched off the device once it was fully set up. The next day I switched it on and the plans were still visible on the home screen, but they had disappeared from the training plan screem. Eventually the plans disappeared from the home screen too.
I reset the device and started again, but the same thing happened.
I have both an Edge 830 and Epix, both work just fine and don't lose the training plans.
Regards,
Jason