If you would like to change the due date and time for several proofs that you own at once, you can do this on your dashboard.
To change the due date on multiple proofs
On your dashboard, click the cog icon.
Select which proofs you’d like to change the due date for by marking them with a tick. You will only be able to tick proofs that you own.
Select change due date, choose a new date and time, and then click change date.
Learn more about managing multiple proofs at once.