You may choose to do either. You will be notified of your upgrade date two weeks in advance. Then, one week prior to your upgrade date you will be able to access a preview of what your account will look like after the upgrade. This will help you become familiar with the new features and layout before the upgrade actually occurs. Once your preview becomes available you can initiate the upgrade yourself at any time during that week. However, if you do not upgrade your account yourself, it will automatically be done for you on your upgrade date.