I read a post [ I think a Gilly post] that stated the Blue sticker coils were troublesome..
So , maybe they changed the center one .

Gilly may see this...

Anyway, check the other plug from that coil... these coils feed 2 plugs and they are in series , so if one acts up, it can affect the other [ if it is the last in the series].... I would expect to see both plugs showing fouling if it is the coil...