Guys! Turns out that they did give us a subtle hint that Fortune’s Weave would include time travel of some kind in the latest trailer.
In the section where they show the MCs portraits at the beginning, the background is a clock.
Fire Emblem Fortune's Weave has dungeons.
But you don't have an infinite amount of time between story beats to mess around. There is a turn limit.
I think Hard Mode is going to be the way to go to ensure you don't over-level quickly.