Sensor battery status now in GC inc. non Garmin

I don't fully understand your point. My screenshots do show ANT IDs..?

See below then refer to top post.

You wrote "You can only pair the HRM Pro to GC". I answered to that, 'cause from that it seemed you connected the HRM-Pro to the phone, not to the watch.

I think we are talking at cross purposes - someone seemed to suggest my non Garmin Sensors may have been showing in GC as they were paired to it.

I just pointed out that its only possible to pair Garmin HRMs to GC so that wouldnt account for the 3rd party sensors showing up. 

Another sensor has appeared today after I used my 'beater' bike to go to the shops - the sensor is only paired to the Fenix 6 Sapphire so that 100% rules it out as being a new feature that came with my 255. It's a generic no-name sensor off Amazon.

Weird, my Sense appears.

I am curious as to why this behaves differently for different people... Are the sensors paired via ANT+ OR BLE (or both...)

OK..so I had a hunch you may have connected your Sense via bluetooth, so I just added a BT connection and...

its un-named but that is how the Verity is connected via BT to my Fenix 6.

I'd seen this on GC Interweb but had not noticed on GCM (iOS). Very useful information to have to hand as opposed to having to dig through Sensors and Accessories to find battery levels.

We've seen this before with stuff going to GCM for some but not for others. As noted sensors need only to be paired ANT+ or BLE to show up. Not sure it's watch specific. As long as the sensors are connected to an active device that has been used within the last 90 days it should be there. 

What version of iOS? What version of GCM? What do you see when you go to More - Garmin Devices when in GCM?

If the option to view sensors is not available, perhaps remove and reinstall GCM to ensure the latest version is picked up.