You can upgrade to Music Maker (MMM) 2023 and run at the same level of features by installing the free version and login in using the emaill address and password used for MMM 2021 - see this tutorial by @browj2
Note: you do not need to purchase an edition if the features of the new edition do not offer anything you would use.
@pete-thomas The 77% off upgrade offer runs until December 7th. This is what the advertisement inside the Music Maker store says. So no need to hurry.
If you have all updates and you use the current version then I think you only miss Song Maker AI and Beatbox Pro 2 and maybe some plugins. If you don't need these features, then you don't need to get the upgrade.