MacRumors published a story that Apple has released the eight betas of iOS and iPadOS 15 to registered developers.
Apple Seeds Eighth Betas of iOS and iPadOS 15 to Developers
Apple today seeded the eighth betas of iOS and iPadOS 15 to developers for testing purposes, with the updates coming one week after Apple released the seventh betas.
Apple Seeds Eighth Betas of iOS and iPadOS 15 to Developers
Registered developers can download the profile for the iOS and iPadOS betas from the Apple Developer Center, and once the profile is installed, beta updates will be available over the air.