https://wccftech.com/wow-shadowlands-assets-battle-net/

WoW Shadowlands assets are now being used in the installation of the World of Warcraft Beta Battle.net client.

Over the past few weeks, several encrypted World of Warcraft Shadowlands alpha builds were shipped by Blizzard and the Shadowlands 9.0 patch also made its way to Blizzard’s Vendor CDN. Unfortunately, due to all of these builds being encrypted, no additional info on the upcoming expansion has been datamined yet.