Upload order of images gets reversed when saved/published

When I upload a series of images to a post in admin through Add Media I get them in their file name order using a convention such as “sample_1.jpg”, “sample_2.jpg”. If I save/publish the post, for some reason the order of the images gets reversed as I get back to the modal window and view the associated images of the post. Why does this happen?
A client of mine uses a lot of images per post (sometimes over 50) and she is not very fond of having to manually reorder them. I figured the best way would be to name them in a convention and let WP sort it automagically as they are uploaded. But this reverse thing breaks the whole process.

Just wanted to add – since she has a lot of old posts from a previous WP version I simply can’t output them in reverse order to realign them correctly.