Normally, you should be able change your Editor's deadline anytime in the Manage page under the Project Info tab.
However, if you are unable to change the deadline yourself, please send a request to our Support Team. When sending this request, kindly include the new date.
Please be reminded, that by changing your Editor deadline, your Delivery deadline changes as well. If you have any concerns about the change of the Delivery deadline, in accordance to your new Editor deadline, please note it in your request as well.