How long can you keep steeped leaves?

Thanks everyone! Great mix of answers. I think I’ll not go overnight. I’ve been making an Oolong/Darjeeling combo in the day and steeping two cups twice (I’ve got a Breville One Touch maker), and making a Green at night – again, two cups twice. If I don’t finish the second 2 cups of Green, I put in a jar for iced tea. Sounds like I wasn’t too far off base. Wonderful thread!