Hi guys, The same happened to me too. And I am using a single location and an administration account.
The issue happened to both a real site I have for clients (where NO item are shown) and one that I have as an example where all the demo items have disappeared, but one that I have added as a try is still showing (so to summarise, in this site just ONCE item is showing).
Both sites menu could be seen perfectly before the latest update last week. Can provide more info if you would like too