You can access an AP via it's IP, but it will just tell you information about it. So you would go to https://<IP>:4343 (just like you would with Aruba Instant On AP's that are compatible to run standalone (200, 300 series). Another thing I noticed is you can't SSH into the AP's as well.
@dippy - There is no option to locally manage Instant On APs. You would need to use the Cloud portal or mobile app.
Are there any plans to add local access to the access point?
@RMA There are no plans to allow local access to the AP's.