I've not had a switch until Animal Crossing New Horizons, and the last Animal Crossing I even played was Wild World for DS, which didn't have much a real sleep/quick start mode like Switch seems to have.
So my question is, what happens if I leave the game running and just sleep the switch for a period of time. Does the game kick you back out to menu so it can re-calculate everything? does the sun/townsfolk/bugs/etc. just warp around to their 'correct' places. What about time triggered cutscenes (housing upgrades, shop changes, events, etc.)?