Unwanted PHRF change in Edit Competitor

When I use Edit Competitor to update records for the new season, the PHRF field will change on its own.
I’m sure it happens when I go to edit the Helm field, but at other times, too. I’m trying to recognize a pattern for the number that shows up,but it’s nothing obvious like previous competitor. 135 is common, but I got a 208
Neither has any significance that I know of.

I’ve never seen this - you can share the .blw if you like and I will see if I can replicate it
Jon