Yeah, I still think he's being "traded off" between "loops." It's Ame's "turn" now so everyone else who knows him pretends they've never spoken to him before so she can have the experience of being the most important person in his life. Before this, it was Itsuki's "turn" and so Umi still has some lingering muscle memories of him(?). That being why Itsuki claims to have never met him yet still acts a bit flustered when talking to him as well as his need to block his number.