You know how it sometimes goes - you're reading a story or relationship build-up and then "wham" all of the sudden everything is in a different place (sometimes literally moving the hero to another locale). Might be because of a new writer or editorial mandate or lackluster sales numbers - whatever. Sometimes those are built up slowly, but sometimes they are abrupt. '90s Superboy comes to mind in some respects, but then, of course, you have the JLA shift to the satellite league and the general tonal shift - but back then, they didn't have the same type of on-going/multi-issue stories to be interrupted.
I'm excluding changes driven by events because they've interrupted the flow of so many comics.
So I'm curious as to which of these seems most extreme or oddest to you (and it would also help to know if you were reading real-time when it was published or later, since I'm curious if real-time reading makes it more or less obvious).