I was just looking at my result from the race I rode yesterday when I noticed something weird going on with the results of a race of 2 weeks ago. I remember getting back to back wins but wierdly only 1 gold throphy was still showing.
When I reviewed the results of those races I found out 1 of the results had be altered again to include a rider that beat me to the line: https://www.zwiftpower.com/events.php?zid=97158 (looking at cat C results)

However it's quite obvious the rider who is in first for cat C (Mikael Strand) is definitely not a cat C rider but a B rider, it's what his power number suggest and what his ZP rating says. So why is a 3.4W/kg rider not filtered out of cat C results?

I took a quick look at some older results and I found a similar issue in this race: https://www.zwiftpower.com/events.php?zid=56348 . Another 3.4W/kg wins cat C... without HR monitor even.

Why are these riders not correctly filtered out?