Yes, Disneyland theme park reservations frequently "open up" as it gets closer to a specific date, often as late as the night before. This is primarily due to the "cancellation culture" among Magic Key (Annual Pass) holders, who must cancel by 11:59 PM the night before to avoid a "no-show" penalty. Consequently, if a park looks "sold out" on a Tuesday, checking the calendar at 10:00 PM on Monday night will often reveal new availability. In 2026, Disney’s reservation algorithms also occasionally release "batches" of tickets for sold-out days if they determine that staff levels or expected guest flow can handle additional capacity. It is a peer-to-peer "best practice" to keep refreshing the reservation calendar on the Disneyland app, especially in the 24 hours leading up to your planned visit, as thousands of plans change at the last minute.