Today I built this 64-bit compatible patch, so that you can try it with iOS 10.2.1 Beta 4. The Beta 4 represents the GM of the iOS 10.2.1 which means that the patch should be compatible with the public release of iOS 10.2.1.
This patch is compatible with iPhone 5S, 6, 6 Plus and probably 6S (it wasn't tested on the 6S yet). Despite being 64-bit devices, iPhone 7 / 5S aren't supported by this patch. The CFW itself can be created using the tutorial I linked in here the description. The video, although made 1 month ago, is still up to date.
Please read the documentation about the Setup.app as well as the F.A.Q. (Frequent Asked Questions) page to understand better how to use this patch or what issues can appear / possible fixes.
Setup.App Patch for 64-Bit iPhone: https://fce365.info/patches/
Setup.App Documentation: https://goo.gl/lzfYUF
F.A.Q. Page (IMPORTANT): https://goo.gl/66sivv
iOS 10.2.1: https://goo.gl/d83B7i
CFW Creation Tutorial: https://goo.gl/jkJlBY