1) initialize submission with two different labels
(for example, use the discogs import greasemonkey to import this (broken in discogs) release :
2) remove one of the two labels and then click "edit note"
3) notice that your "edit note" page contains both, including the one you removed
4) click "release information" try to correct, notice the erroneous one is not on the first page
5) click back to edit note.. and see it there again..