You can use most of the features of the Bonvoy app including check-in but as @hedberg1661 indicated above the Swan & Dolphin don't participate in the Bonvoy electronic room key function as of today. They have not upgraded the room door locks and systems to support this feature.Has anyone used the Bonvoy app to check in at the Swan?
Was 11 PM your original check-in time or are you being delayed by travel? The Bonvoy app allows you to chat with the hotel team directly on the way to the resort.
Dave