I would believe that to be correct. We used a squat switch to change to alt mode based on an airspeed switch, and we only did one or two of them. In the most current rev of the TT22 install manual that we have, which is May 2015, it only refers to it and I believe it says " if equipped ". I would guess that later software gives you the option of setting to to GPS based speed such as what Garmin does. I am not sure who handles Trig tech support here in the United States, I think it is Mid Continent. I also cannot say if they will assist an end user or if they will refer you to a dealer.
Mike Sutton
Cubcrafters Avionics
Thanks Mike & Paul. I've just had a reply from Trig support saying the software only supports automatic ground/air switching since March this year.
They provide free software updates through the Mid-Continent locations.
So I'll live with it for now and get the update done when convenient.