Thomas Cook is a package holiday company that often offers open seats on their flights UK-Europe (and occasionally US and other countries).
Seat maps here:
https://www.seatguru.com/airlines/Th...s_A330-200.php
Will be no-frills - would think pay extra for bags/food etc.
Also think they are still charter flights as against scheduled - so if a problem may not be another until following day/week.