Over North America and Europe, usually when airliners go east (heading 0-179) they cruise at a flight level with an odd number (e.g. FL370) and when going west (180-359) they cruise at an even number (e.g. FL380), right?
When looking on flightradar24, all planes follow this pattern except for planes flying over south-west Europe (Iberian peninsula, Cote d'Azur, Mallorca and so, as well as Morocco): there, planes flying to the east cruise at even numbers and to the west at odd numbers. Why do planes flying over or near the Iberian peninsula have the flight levels inversed?