Just an FYI as its something that has been driving me crazy for a few months now.
I have three 24TB Netgear 516 boxes, two local and one remote. Previously I used Bittorrent Sync to backup the main server and generally speaking a 30G folder would be synced to the satellite NAS box overnight - fine
Upgraded to Resilio, well, for reason unknown, Netgear doesnt allow a straight forward upgrade to ResilioSync I had to start again.. It all works again but the sync was SOOOOO SLOW, it was quoting over 1000years to complete at once stage, the speed was in a few bytes per second. Suddenly too my syncing was via a relay server, it wasnt before.
Anyway to cut to the chase the last update by Netgear (there have been a flurry of updates recently) to 6.9.2 all is transformed, with no other changes to my firewalls or network, the sync speed is back up to Megs per second and the sync time remaining is in days - Hurrah
No idea what Netgear have done but it certainly stopped me from throwing it all out the window, if you are on Netgear, then if for no other reason, upgrade to get the sync speeds back up