Yes, there are still plans to add fixes for 2010/2012 CPUs in a future update. I don't think there is any need currently for more crash reports on these CPUs, and the beta branch (on Steam and GOG) has not been updated since the 2013 AVX2 fixes were moved to the public release. If needed it will be updated at some point and another call for beta testers posted.
For GOG the beta is only available through Galaxy, since GOG only makes the full installers for the main branch releases.
