There appears to be 2 definitions of 'regulation' in play. Certainly poi for both double rifles & shotguns was perhaps the prime use. Howevever in the case of the op, he had a patterning problem which was 'perhaps' remedied by his gunsmith adjusting the chokes. Nothing said about moving the poi, or for that matter he did not appear to claim that there was a poi problem.
In my limited experience adjusting chokes to give the desired pattern has been called regulation, patterning, and plating. With 'regulation by far the most common term.