Garmin GTX 45R ADS-B Flightplan Category

Garmin GTX 45R ADS-B: What is the flightplanning category for ADS-B? It's 1090 Hz but is it B1 or B2? Can anyone give me a little color on this issue?

It's /E for the transponder type. For ADSB I use B2 but as you've found there seems to be no code for what many of us have: both 978 and 1090 ADSB-IN.


Edit: from the FAA's guide to ICAO flight plans:
B1 1090 MHz out capability, or
B2 1090 MHz out and in capability
U1 UAT out capability, or
U2 UAT out and in capability

I use B2 as well - it has both 1090 in/out. Also has 978 in…
That said, I think they’re more concerned with your “out” than “in”