I think it's pretty clearly a stable time loop
What makes you say stable time loop over route hopping?
Mainly the fact that this time travel part is filling in the previously mentioned blanks in Evie's memory, which would imply that she did not have these memories because the time traveling version of her was in control at the time. That, and as we are seeing right now, she's also laying the groundwork for Elsa going for her instead of any of the original male love interests, explaining this particular already seen change in the story's direction.