MacRumors published a story that Apple has released the second release candidate of iOS 14.3 and iPadOS 14.3 to registered developers.

Apple Seeds Second Release Candidate of iOS 14.3 and iPadOS 14.3 to Developers

Apple today seeded a second release candidate version of upcoming iOS 14.3 and iPadOS 14.3 updates to developers, just two days after seeding the first release candidates and a month after the launch of iOS and iPadOS 14.2. iOS and iPadOS 14.3 can be downloaded through the Apple Developer Center or over the air after the proper developer profile has been installed. Today's update has a build number of 18C66, while Tuesday's RC had a build number of 18C65. 

Apple Seeds Second Release Candidate of iOS 14.3 and iPadOS 14.3 to Developers