Cubase 4 - update or upgrade to Cubase 10.5?

So I’m looking to upgrade to the latest version of Cubase and as far as I understand, an update would be for example, from Cubase 6 to 6.5, and an upgrade would be from Cubase 6 to 8. However on the Steinberg website it gives me the option of an UPDATE from Cubase 4 to 10.5. Can anyone clarify what the difference is between the update and upgrade? Thanks :slight_smile:

UPDATE is within the same version range. I.e. from „Elements x“ to „Elements y“, „Artist x“ to „Artist y“ and so on.
UPGRADE is from a lower version to a higher version. I.e. from „Elements“ to „Artist“ or „Pro“, or from „Studio“ or „Artist“ to „Pro“.

Thank you!