We've already heard word of an Android 4.4.3 update already in the works, but now we're seeing hints that the release might be coming soon. An app maintained by Google under its Education endeavor was just updated to add, among other things, support for Android 4.4.3.
The app itself, called the Google Edu Device Setup, won't probably be of much interest to most end users, unless they're part of the Google's Education program. It is practically a tool for Google Education administrators to setup and manage tablets that were bought from the program, allowing them to simply copy approved configurations to devices instead of manually tweaking each one. The new update opens up the app to even non-Nexus tablets and, as mentioned, adds support for Android 4.4.3.
Up to now, the exact details of this upcoming Android version are still shrouded in mystery and, therefore, rumors and leaks. The most that we can say about it is that, given the version number, it will most likely be an incremental upgrade and we should not expect groundbreaking changes. Then again, Google has been known to break a few conventions when it comes to version numbers and releases, so we're still expecting the unexpected.
Though this app does confirm the existence of Android 4.4.3, it doesn't really give us a more solid date of when it will arrive. Given that Google I/O will soon be upon us, it is probably reasonable to expect that it will roll out around that time to take advantage of the hype around the event.