"Over and Out" is NOT part of contemporary ICAO R/T (perhaps when you were flying but not now)
Bloggs,
Of course it bleeding well isn't, and hasn't been for gawd knows how long, approximately since VHF took over from HF as the primary voice communications --- but that's probably a bit before your time.
But--- the ICAO Docs. do explain the use of the aircraft call sign at the end of a transmission, and its derivation from 'Over" and "over and/out" --- and that, is the whole point of my comments, as any normal reader would understand.
You should try a bit of flying in the US, it might surprise you.
Aviation in Australia would be vastly better of if we emulated all the good things about aviation on the north American continent.