The wording of it all can lead to confusion but cloud saves is a console feature, rather than a game-specific function like the upload/download. You may not have it turned on, on 360. I don’t believe it’s automatically on.
For the sake of clarity, go to your 360 and follow this:
Settings - System - Storage (on this screen you should see Hard Drive, and Cloud Saves). Highlight Cloud Saves and press Y for device options, and select enable. NOTE You must have Xbox Live Gold to use this feature.
Once you have enabled Cloud Saves, move to your hard drive and locate your Borderlands (or any game you want to use on the Xbox One) save file, Press A on it and select either Move (if you don’t intend to use it on your 360 again) or copy (if you may use the 360 again) and select Cloud Saves as the destination. This will upload the save to the cloud, allowing you to access in on the Xbox One. When you load the game up next time (via Xbox One), you will get a box pop up saying it is syncing Cloud Saves.
If you Move something by mistake you can still copy it back from the cloud saves in the same way you moved it to the cloud but select Cloud Saves first, instead of Hard Drive.
Sorry for the wall of text, but I hope this makes it clearer (maybe not)