I actually didn't hear that one but that would also make sense. FKA Twigs cancelled her festival dates in late February, including Oya the week before GM, so it kinda made sense that it would throw GM into flux just before their announcement. You probably have more of an inside scope than me though. She's been on 6 Music this morning, which was a treat. Y
Regarding Khrungabin, I do agree if it sells out but I'm pretty sure PJ Harvey didn't manage to. Boygenius played Connect Festival the same year as Gunnnery, which is roughly the same capacity as GM. Khrungabin are also playing Piece Hall in Halifax, which has had GM alumni Michael Kiwanuka, FJM and PJ Harvey before. All I'm saying is they're not a write-off!
But also, I have never successfully predicted a headliner so I may well have cursed all three of them never to grace Glanusk.