Darryl, thanks. I did not know that “All popular PDA/PNA software that
I am aware of is capable of (and flight computers that support
airspace all) will work with pressure altitude.”

So I was seeking clarification.

I use Volkslogger and Winpilot, set up and connected by an agent/
vendor. I really don’t know the technicalities.

There was some correspondence recently on the (mainly UK)
gliderpilot.net which caused me to raise the question.

Regards – Chris.