Rey was here, but it must've been ... she didn't know I was alive, either. [he shakes his head.] She had my jacket, and gave it back to me. [maybe he's wearing it now. maybe now because of timeline shenanigans they have matching jackets.]

I think it has to do with the portal. It can pull people out of different worlds, but it can pull people from the same world out of different times, too.