Sefaketen
I don't have the document to hand but I think it's to do with where the tracks "slope" that is where they are inclined. I wondered the same thing re 25 vs 30 nm separation.
andmus
Re contingency a subject of much discussion currently. As I understand it turnbacks prior to getting approval need to be out of MNPS airspace. My take on that is below FL280 so down to FL275. I'm not sure if the appropriate ICAO doc is up to date. If anyone has a link please put it up here.
BBK