This was accredited to FB. What basically happened is that my CDG - WAW part of the journey, which was rebooked, earned twice the amount of miles than my AMS-CDG, CDG-AMS, and WAW-CDG, which combined led to way more miles than what I paid for. It could be luck, but it earned me 250 more miles than what I roughly should have earned, based on €4/mile, excluding the taxes and surcharges.