In reply to M1MAJ:
I think your descriptions sound just about right Martyn. in my view the use of /P or /M should portray the kind of station setup. So the vast majority of my SOTA activations are /P with a fishing rod either tied to a fence or supported with guys; not the kind of thing you can just move. Whereas people using something like an MFD and radio from a bag whilst standing by a trig point could equally be /M or /P.
Never heard a /A but I’ve worked 2 /MM stations in 20+ years of activity. One was the QE2 about 17 years ago and the other was from the summit of White Coomb the other week.
MM0FMF/W (well I’m in the office at work not at home as I was earlier!)