Well, turns out the error is even stranger. The Itch.io sent email with the september update mega link inside I got? It has the subject tile "july update is here!" with no mention of September. Which is why I swept it up with other 'Just news updates' emails. "Wait a minute... Why is this under her command july update email dated yesterday *opens email to see it talking about september*... ARE YOU SERIOUS!?"
Will edit my first comment shortly to make it clear "Double check your under her command emails, it might look like a useless july email". Just leaves the question "Pure Itch automation mistake, or Dev accidentally forgetting to change the subject line for the new build?"