That is correct and updatable meta data will also reflect the new folder location however you cannot guarantee to catch everything as users delete shortcuts so there is no guarantee,
You can use EVPM to associate different Retention Categories to different folders and the updatable mettadata will then inherit the new Retention, but take "Deleted Items" for example there will be millions of shortcuts deleted from the Deleted Items so will therefore not get updated, and will still have the "default" Retention Category set.
--wayne