In Aha you use a number of different date formats and it can be a pretty confusing where there's really no need for it to be. For instance (for me in Australia), in the slider at the top of the releases roadmap it is yyyy-mm-dd. In the header of the same page it is ddd mm (no year). If I click into the details of a release the "release date (internal)" is dd-mm-yyyy but right next to it is the external date is dd mmm, yyyy.
Thank you for the note. This inconsistency is intentional as we use the best date format based on the circumstance.
We primarily use two layouts: "May 13, 2016” for dates that are read only. And “5/13/2016” for dates that are editable. We don't use "May 13, 2016” for editable dates as this would be difficult to type correctly (we plan to add capabilities to support typing dates). However, "May 13, 2016” is more readable in reports which is why this is also used.