Where do I change how often the app checks my Supernote and pushes to my task apps?

Open the Scheduling section (the "Scheduling" item in the left navigation, labelled "Sync & push schedule"). It has two cards: "Device & cloud sync" controls how often the app checks your Supernote for changes, and "Push to task apps" controls when your tasks are handed off to apps like Todoist. Each card has a Manual/Auto toggle, an "Every [number] [minutes/hours]" stepper (shown only in Auto), and a "Sync now" / "Push now" button. Below them, the "Active hours" card sets the days and times when those Auto schedules are allowed to run.