Beta 1 of iOS 13.3 and iPadOS 13.3 Released for Testing
Apple has released the first beta versions of iOS 13.3 and iPadOS 13.3 for users enrolled in the beta testing programs.
Typically a developer beta version rolls out first and is soon followed by the equivalent build as a public beta.
Separately, Apple has released new beta versions of tvOS 13.3 and watchOS 6.1.1 for Apple TV and Apple Watch respectively. There is not yet a beta version of MacOS Catalina 10.15.2 available, but presumably one will be issued in the relatively near future.