BUG: If HRM Pro is set to provide Speed and Distance for one watch, other watches do not recieve running dynamics

I used an HRM Pro connected to 4 (yes 4) for an experiment (see https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-6-series/301347/hrm-pro-fw-8-80-or-plus-for-improving-distance-and-pace-related-problems-for-outside-running-on-the-f6)

I have noticed that Running Dynamics were missing from the Fenix 6 and Fenix 7.The 255 DID get running dynamics.

All were connected by ANT and the HRM Pro shows in the activity summaries as being connected.

Running dynamics are missing (therefore no power either)