Detecting iPhone absence via UWB on macOS

I'm developing a proximity tool on macOS Tahoe 26.2 (M4 MacBook Pro) to detect when my iPhone leaves the immediate vicinity of my macbook.

Does NearbyInteraction on macOS support persistent background sessions for detecting peer absence (didInvalidate/timeout), or is CoreBluetooth still required as the keep-alive trigger?

Detecting iPhone absence via UWB on macOS
 
 
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