Having had the honour, only once thankfully and not against me, of "speaking" with the CAA's enforcement branch I would argue that they are a very professional crowd.
The majority of them, so the guy said, were ex-Transport Police or CID.
I did get the caution. It was in the days pre-"not speaking will mean you are guilty". Therefore if he didn't caution you I'd say it's either a) a wind-up or b) you flew over the Chairman's BBQ and he saw your registration.
In regards to the PACE, I believe that in all circumstances where a prosecution is likely, whether against you or not, the interviewer has to read you the spiel. Otherwise you could perjure yourself and not be aware that you were doing so.
I'd get onto them (I think they're based in Gatwick, so why the Kingsway number??) and ask to speak to the Head of Department and report your concerns. If it wasn't them you'll find out, and if it was, ask them to put it in writing. And then watch your back forever.....
