By default, Addenda are ordered in the sequence in which they are created/uploaded i.e. oldest at the top, most recent at the bottom.
Addenda can be re-ordered by clicking RE-ORDER under the Addenda tab.
Click on the Addenda you want to move and drag it to the place you want it to be.
Once you have completed the re-ordering, click SAVE to save the changes.
Alternatively, click CANCEL to close without saving changes.