Simples! They had to take an aoc there becouse it's a special country with special rules.. After that they closed donetsk base becouse of the political issue and relocated everyone and now they operate only form kiev. You need an ucrainian licence to fly and onestly if you come from western eu, never visited the place and don't have a clue what your getting yourself in, I suggest you stay away before you turn your life upsidedown..