MacRumors published a story that Apple has released the first betas of iOS 14.4 and iPadOS 14.4 to registered developers.

Apple Seeds First Betas of iOS 14.4 and iPadOS 14.4 to Developers

Apple today seeded the first betas of new iOS and iPadOS 14.4 updates to developers for testing purposes, two days after releasing the iOS 14.3 update that brought support for Apple Fitness+, AirPods Max, ProRAW for iPhone 12 models, and more. iOS and iPadOS 14.4 can be downloaded through the Apple Developer Center or over the air after the proper profile has been installed on an iPhone or iPad.

Apple Seeds First Betas of iOS 14.4 and iPadOS 14.4 to Developers