When you license REV23 software you get updates and support for 12-months after your purchase. If after this time we release a new version you would like to use, you can optionally upgrade your license for a fraction of the cost of the original license. The upgrade entitles you to another 12-month period of updates and priority support. If your license has been expired for more than 6 months, you will need to license the software at its original price, or obtain a subscription if you wish to upgrade. Add-on PC licenses do not need to be upgraded annually.