HarmLessSolutions:
Don't know how the Atto3's headrests are fitted but in a previous car we pulled the HR right out and refitted in reverse for my partner who found them uncomfortable. The HR just had 2 shafts that slid down inside the seat, so reversable.
The seat back including the headrest is all one piece. Same in the Seal and Sealion, and I assume, the Dolphin. Cheaper I guess.