The quote is still on the cover of the published book but it's missing from some of the publicity photos.
If I were a betting frau, I would say he's softly, gently cancelling her, not by a big public spat, but just quietly, behind the scenes. I'd further say it was something to do with the literary festival in September where he was supposed to interview her, she turned up hours late, and they had to fill in the gap with interviewing someone from a local foodie business who happened to be in the audience.
He hasn't interacted with her on Twitter since then, anyway.