https://wwos.nine.com.au/cricket/ic...air-play/36f769e6-c7ed-4b26-96e6-a9553f16f953
"at any point before he releases the ball provided he has not completed his delivery swing." is much more difficult for the umpire to judge.
In this incident it was refered to the TV umpire. The TV umpire confirmed that the bowler hadn't completed her delivery swing and that the batter was out.
Like you I have my ACAS qualifications and did a lot of umpiring. I have seen umpired a few incidents of the non-striker being run out in this way. Usually, but not always, the bowler would warn the batter first and only complete the runout if the latter persisted in leaving the crease early.