I've had a few issues with connecting sensors via ANT+ recently, which seems to be when they're connected to my phone via bluetooth.
Garmin HRM Pro. Disconnected and then didn't show up on my 1040 until deleted from my iPhone.
Speed Sensor 2. Random connect/disconnect until removed from my iPhone.
Epix Pro HR ANT+ rebroadcast. Tried this when I lost connection to my HRM Pro, but wouldn't connect. Didn't delete it from my phone as it needs to sync all day, but guessing its the same issue.
So do sensors disable ANT+ to save power or something when connected by Bluetooth?