I believe once you hit the submit button and add the game it will show up. I hope that helped.
Viewing post in I unintentionally submitted an old game
We just implemented this feature this game jam. You as the submitter should be able the edit the project since it makes it's own itch page. I believe tho, the edits should reflect the game subbed in the game jam. Submissions aren't locked so editing is allowed. I will test this out later as well to see what is happening.