Virgin London Marathon announced a restriction to its Good For Age entry requirements today for men.
Previously you only had to run under 3:05 to be guaranteed a spot. Now you need to run under 3:00 (for 18-40yr olds) and it isn't guaranteed - only the first 3,000 entrants get a place. No change to requirements for women.
More info here: https://www.fastrunning.com/events-and-races/events-news/london-marathon-changes-good-for-age-qualification-for-gender-parity/14861