That's outrageous. Even though I say they were NOT for circulation, they are legal tender, so it's possibly unlawful for banks and the RM not to change them for other currency.
I think we may be using the words 'circulation' and 'currency' in different ways? It seems possible to me that you mean a coin that's neither a proof, specimen, or pattern would come under those headings? Whereas I mean that a coin that was not struck / issued to be spent by Joe Public in shops or other transactions (i.e. not part of the money supply), is neither 'for circulation' or 'currency'. By my usage, Wreath crowns (for example) were not under any circumstances struck for circulation or the mintages would have been significant, and we have it on record (somewhere) both that the Treasury abandoned crowns as an everyday denomination in the early century, and that wreath crowns were only issued in very small quantities to collectors and their ilk.
The 1952 halfcorwn is a very interesting case. It is EITHER a pattern (only one ever having been struck) OR is the sole survivor from the beginning of a currency strike of 1952 halfcrowns, the rest of which were melted down when the King died. In which case - and given that the unique specimen DID circulate - it could be regarded as a circulation coin. It's certainly true that if the King hadn't died, 1952 halfcrowns would have been issued. In any case, it's not a crown!!
I'm not sure what you mean by 'strict definition'? I'd still claim that a 'first year of reign' is a commemoration. What else would you call it?