Whether the GLRM can be charged continuously over USB-C while switched on and operating, without affecting GNSS, Bluetooth or RTK performance.
Yes, the GLRM can be charged while operating. Charging does not affect GNSS or communication performance.
Whether the current USB-C connection exposes a supported data or serial interface, or whether it is charging-only.
Currently, the USB-C connection is used for charging only. It is planned to add support for serial communication over USB-C in the near future through a firmware update (the hardware capability is already there). The commination capabilities and protocols will be very similar to Bluetooth Classic.
Whether the receiver can be switched on or awakened through USB-C or serial?
If remote power-on is not currently supported, whether automatic startup when external power is connected—or another firmware-controlled option—would be technically feasible.
Yes, the GLRM can be powered on (and also powered off) via USB-C. The detection is based on charging power, so the GLRM can be configured automatically turn on once USB power is provided. This feature is only available since firmware version 1.11p2.
It is also possible to configure the touch power-button so that even if a touch is detected, the GLRM only powers off it the GLRM has no satellites visible or is not connected to a phone.