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.
Did anybody actually watch this live? I'm only asking this because was Charlie Dean warned by the bowler about encroaching up the crease? I know when I've played, I've heard bowlers say "If you do that again, I'm taking your bails off" At the end of the day, it's not against the rules, it's just frowned upon, stop whining.
That's OK when you have a TV umpire, but rather more difficult in a club game. In my opinion almost all the law changes since 2019 are, at best, ill advised. The MCC seem more interested in international cricket and the TV, than the grass roots game.
