It looks like Microsoft is not going to (publicly) give up on Windows 10 Mobile anytime soon. The rumours had suggested that Windows 10 Mobile won’t be getting the Fall Creators Update and it seems to be technically correct.
After Microsoft released Windows 10 Mobile Creators Update, the company separated the mobile operating system from the development branch. Since then, Microsoft is releasing Windows 10 Mobile preview builds from the new feature2 branch. The latest preview builds have only improvements, bug fixes. The same update is coming to the general public after the PC release which is scheduled to roll out on October 17.
The feature2 update is technically the Creators Update, the feature2 basically puts all the existing phones on an extended life support. Windows 10 Creators Update has the version 1703 whereas the Fall Creators Update comes with version 1709. Windows 10 Mobile was receiving builds from the feature2 branch i.e the version 1703 of the operating system.
However, Microsoft has recently released a new build 15252 for Windows 10 Mobile that changed the operating system version to 1709 from 1703. It appears that Microsoft is going to address the minor feature2 release as the Windows 10 Mobile Fall Creators Update. Microsoft is actually going to rename Redstone 2 (Creators Update) (and now feature2 update) to the Fall Creators Updates.
Still, no new features from the actual Fall Creators Update is going to be introduced for the existing phones. Windows 10 Mobile is technically going to receive the Creators Update with more fixes. The good news is that Microsoft will probably support the existing phones for more time as after all the phones are being updated to Windows 10 version 1709 aka the Fall Creators Update.