downgrade
A downgrade refers to the opposite process to an upgrade: a technological advance that was available with a product is revoked. The term "downgrade" is very common in connection with computer software and refers to the withdrawal or suppression of previously used features.
The right to downgrade, i.e. the right to use an earlier version of the same product instead of the currently licensed version, is limited in software trading: it applies exclusively to volume licenses. Furthermore, there is also the so-called version downgrade, i.e. the 'step back' from a professional to a standard version. Here, too, the downgrade right is not generally given, but must be expressly included in the license conditions of the software.