what are the GPS "mode change" event message codes?

DC Rainmaker documented this series of events for GPS mode changes in the FIT file?

This is neat, I was not aware that was recorded? Apparently that was in a Fenix7 series so I assume it survived to F8 and F9?

Is it recorded in the single-band models?

Would definitely like to decode those, curious of BeiDou is being used in continental US (hope so)

ps. any chance a CIQ datafield can watch for these events in realtime and show on the screen the GPS band status?