The UPGRADE button on the Stay Card will only be available on the day of arrival or the day before arrival, depending on what settings you've configured from Settings > Promos & Upsell > Upsell Rooms > Daily Upsell Room Level Targets.

 

If you would like to change the room type after the day of arrival or day before arrival, you can click the orange >> next to the room type to be directed to the Room Assignment screen. From there, click the dropdown menu for the room type and select the new room type. 

At the bottom of the page, there will be a green CHANGE ROOM TYPE button. You will then be prompted to choose NO CHARGE or add the upgrade value (if there is one). You can do this at any time.