After buying upgrade license from Parallels 20 to 26, will version 20 license remain valid?

I have a permanent license to Parallels Desktop Standard version 20. If I purchase a license for the latest version 26 at the upgrade price, will my existing version 20 license key be invalidated or deactivated? Or will it remain valid? In other words, will I then be able to use both versions 26 and 20 on two different computers?
--Ron