This isn't a change as far as I can tell - all catchment children scoring 334+ (including adjusted scores) will get a place unless there aren't enough places. And in 2020 there is a PAN of 202 (compared to previous 173) so they have a better chance than previously.
See
https://www.agsb.co.uk/media/95086/2020 ... policy.pdf - see point 7, oversubscription criteria. If there are too many catchment children who pass, they are ranked by distance from the school, not by score. The only children ranked by score are those outside the catchment area.