I have just upgrade SS from 2.4.0 to 2.4.6 by using the following steps:
1. Deleting the cms and sapphire directories
2. Copying the new cms and sapphire directories from the downloaded 2.4.6 folder
3. Completing a http://www.mysite.com/dev/build/?flush=1 to rebuild the database.
Everything seems to be fine however in the CMS down the bottom left where the version is displayed it is blank.