I hadn’t heard of Cal Calamba but having now read the Wikipedia page I might imagine Cal being v upset about this turn of events.
Presumably Cal wasn’t allowed (or wanted to?) enter the female category because of taking CSH, but knew that Cal would struggle to make entry in the men’s category because of sex-based differences.
Now, having campaigned hard for marathons to include a new NB category, it must be upsetting for Cal and other genuine NBs to suspect that an AMAB runner is not really NB but is pretending to be one to gain access to resources previously exclusive to genuine NBs.
"the interim system may be vulnerable to good-faith loopholes, scenarios where runners register in a category not as an expression of identity, but as a way to meet easier entry standards"
It might even be enraging that this brand new NB entering the NB category could end up winning all the prize money in that category. And yet, I’d place any amount of money that when it’s pointed out that men can exploit gender ID for not nice reasons is precisely why women do not want any man to use ssss, Cal and co would say "that’s different!".