If you purchased a single or 2-5 sites license you can upgrade your license to a higher package with following the steps below. You only pay the difference of the lower package compared to the price of the higher one.
To do so log in to Your Account.
Click on View Licenses:
Then click on View Upgrades:
If you upgrade your license key we’ll use a true time-bases proration which means that your upgrade will cost you only the difference from Plan A to Plan B related to the time left of your license expiration time.
To get updates and support for another year you additionally need to extend your license. If you extend your license expiration time left over will be added to the extended extra year.