Our current release notes mention versions to our products when applicable. Since Adobe Analytics is a SaaS solution, there's really only one version available - the current one. We have regular maintenance releases each month to update our web UI.
There really isn't a "version" for the web UI of Adobe Analytics. There are AppMeasurement library versions, and Report Builder's plugin has a version, but Adobe Analytics in general does not.
In the fall of 2016, SiteCatalyst 14 was end-of-lifed (discontinued). This means that all access to the SiteCatalyst 14 user interface and several related features was removed. You must log in to Adobe Analytics/SiteCatalyst 15 (latest version) or log in via the Marketing Cloud.