All,
As I was on a roll, I pressed forward from 3.8.2 to 3.9.0, and have posted a BETA GR-3.9.0.0 package for Windows 10.
A couple key caveats:
1- There is not an actual .msi installer file, the msi WIX created began to fire 2907 errors due to some strange vccor dll issue, so this is merely a ZIP file that can be unzipped where you desire. The only real downside is that there is no shortcut cleanly placed in the start menu. RUN_GRC.BAT found in the /bin folder is all you need to remember.
2- gr-soapy and gr-osmosdr were built from non-official repos that have already added some 3.9 support, so your mileage may vary.
So please poke around with it and post your bugs. While in theory the 3.7/3.8/3.9 packages could all be installed simultaneously, there are some potential issues with the user-specific configuration files causing problems (as all 3 installations share the same "per-user" config).
Once a couple more OOT packages become officially compatible, a full installer will be release "soon" afterwards.
Geof