OP - keep in mind that AF overbooks its economy and premium economy cabins often. Especially the 3rd week of December, when leisure travel is peaking and business travel is lower than usual.

This results in a lot of OPUPs and moving around the cabin of various folks; you might see 58 seats now, but I've been on AF flights were economy is overbooked by 30-40. All those people have to sit somewhere.