I have three iPads, an iPad 2, and iPad Mini, and an iPad Mini Fourth-Generation. The problem I am about to describe only exists on the iPad Mini Fourth-Generation. PLEASE fix it.
The problem is that I frequently update saved PDF files with newer versions of themselves. On my other two iPads, whenever I move or share a new version of an existing PDF to Adobe from an email attachment or from another program on my iPad, the program puts the new file into the top folder level of "On This Ipad" and when I attempt to move it from there to the subfolder where its predecessor version is filed, it recognizes the prior existing copy (because it has the exact same file name) and asks if I want to replace it. If I say yes, it simply eliminates the prior version (which makes life easy).
Unfortunately, it does not work in that simple and quick way on the iPad Mini Fourth-Generation. On that iPad, while you can move or share a new revised version of a file to the top level of Adobe's "On This IPad" (coming either from another app or coming from an email attachment), if you try to move it from there to the Adobe sub-folder where it's older counterpart exists in order to replace it, it will not do it in a way which eliminates the need to go back and manually delete either the old file or a duplicate version of the new one. The problem arises regardless of whether you "move" or "share" the new file to get it out of "On This Ipad." If you click on "Move", Adobe will delete it from the top "On This Ipad" level, but will create a duplicate of the file (followed by the added designation of "(1)" at the end of the file name in the desired sub-folder, and will not replace or delete the older version you want to eliminate. If, on the other hand, you try to use "share" to move the file from "On This IPad" to the desired sub-folder, it will indeed give you the option to actually replace the older no-longer-wanted version of the file in the sub-folder, BUT it will leave an unwanted duplicate copy of the file up at the top "On This IPad" level which you then have to go back and delete.
Since these laborious requirements are not present on your other iPad versions of Adobe, I am begging you to fix the version you have for the iPad Mini Fourth Generation so it will work as quickly and simply as the others to replace earlier versions of the same files.