Microsoft has announced the long-awaited ability to run emulated 64-bit applications in Windows on ARM. This new feature will allow applications to use more memory and thus gain better performance than their 32-bit counterparts. The feature is available in the Windows 10 Insider build 21277, which was released yesterday to Insiders on the Dev channel. Microsoft has still not stated when this feature is estimated to go live, and we should expect to see this tested over the next few Windows 10 releases.
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-adds-64-bit-application-support-to-windows-10-on-arm/