The Adventures of Middle Earth game had either a baseline system or variant (it's been a while since I read it, so it's possible I'm off) where rather than "adventuring day," the period of measure for a lot of abilities was "per adventure," and the encounters that take place don't necessarily take place in the same day but rather the span of an "adventure" or mission, and that flexibility and scope seemed to be geared to set-piece encounters/events and the resource management over a period of time. The system has a definition/confines, but you could flex it, and it seems to coincide with the rest variants on longer long & short rests.

I've said this before, but the design of 6-8 encounters-worth of challenge a day is insane and doesn't feel connected to the reality of at-the-table execution. I have a blast running high-threat single adventuring days in some of my more typical "dungeon" material over multiple sessions, but it's hard to do larger narrative/scope coverage without losing the tension and resource management aspect and meddling with the overall design of ability availability/recharge.