The backlog is sorted by the rank field and there's no other option to change this. Also, I believe that this case is related to the following BUG, which can be useful to understand this case:
Hi all Lets make this Friday fun really fun and post one (or more) of your best jokes! The joke can be about an Atlassian product, or just a really fun joke you want to share! I’m not the best j...
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