No. It’s 4PM because it’s at that point that it cannot be clawed back. Monzo could pay you at 1PM/2PM/3PM but if the money was reclaimed at 15:59, Monzo would be on the hook for it. So it’s 4PM.
And it might be two years since the suggestion, but it’s got 4 votes in that time, so clearly not popular or a big annoyance to many.