Apple has seeded the release candidates (RCs) of macOS Big Sur 11.5, iOS 14.7, iPadOS 14.7, tvOS 14.7, and watchOS 7.6 to Apple developers.
A release candidate (RC), also known as “going silver”, is a beta version with potential to be a stable product. Registered developers can download the betas via Apple’s developer portal. Or they can be downloaded over-the-air once the proper configuration profile has been installed from the Developer Center.