MacRumors published a story that Apple has released the third betas of iOS and iPadOS 13.6 to registered developers.
Apple Seeds Third Betas of iOS and iPadOS 13.6 to Developers
Apple today seeded the third betas of upcoming iOS and iPadOS 13.6 updates to developers, three weeks after seeding the second betas and over a month after releasing iOS/PadOS 13.5 with Exposure Notification API, Face ID updates, Group FaceTime changes, and more.
Apple Seeds Third Betas of iOS and iPadOS 13.6 to Developers