I wanted to change the flight date, but it is a n8ghtmare to contact customer support. They have no clue about being nice to their customers or doing their best to help them. While on email and social media I'd gotten rigid, standard replies that helped me 0, on the phone they take forever (and never) to answer, especially if God forbids you are abroad so you're basically doomed.
The 3 categories of flight are not a good deal, especially if you buy the second two ones which are more expensive (maybe to get the flexibility of a bigger luggage or partial/full option to change flight dates) you don't feel you are buying a low cost ticket. Compared to other low cost companies, they pretty much suck.