Update: A new version of Windows 10 Update assistant has now leaked and it allows to upgrade to Windows 10 Creators Update. If you are on Anniversary update Build 14393 you can upgrade to RTM Build 15063 using this tool.
Windows 10 Update Assistant for version 1703 has leaked on to the internet and provides Windows 10 users a glimpse of how Microsoft would be looking to push the Creators Update on your machine when official roll out begins which is set to take place in a few weeks from now.
Like the Anniversary Update, Windows 10 Creators Update won’t be available on day one for all the 400M+ devices running Windows 10 and it will take time for your machine to see the update, download and install it. With this in mind, Windows 10 Update Assistant helps impatient users to download the update early to secure the systems and enjoy the latest features and improvements. (Read full detailed Windows 10 Creators Update changelog)
One interesting find about the newly leaked tool is that on running the tool on your machine with the Anniversary Update Build 14393 and above, it offers you the Creators Update Build 15063 (see screenshot above) which is the latest insider build available for PCs both on Fast as well as the Slow Ring.
You may go ahead and ask the tool to get you the upgrade, but it does nothing at the moment and stays at 0%, which is not surprising at all.
This further strengthens the fact that one may consider Build 15063 as the final RTM build, but Microsoft has yet to confirm and might consider releasing yet another build to insiders before finalising.
If you are willing to give it a try, download it from here