FR/LG : PKHeX not registering flags for Blue (Champion) battles

[Asia81]

Hello,

I'm not sure if I did something wrong or if it's working as intended (in which case, can you tell me why, please), but I noticed flags for the Blue (Champion and Rematch) battles are not checked in PKHeX, happens both in fire red and leaf green. Work fine for all others Blue battles.
In case you ask, yes I sure did them at least once as I beat the elite four 200 times (manually, it was so long...) to get the stickers on trainer card.