I have managed to solve some issues my end and got Acrosync working which is brilliant. I have a setup as follows -
1 x OVH Server 100Mb upload/ 100Mb download
2 x RN104 NAS 10Mb upload / 50Mb download (separate locations internet speed same)
1 x RN102 NAS 1Mb upload / 5Mb download
Centralized backups are made to the OVH server daily, each set of drawings is around 5GB and there are nearly 70 separate folders on the OVH server. Currently the OVH server is uploading at only 204Kbp/s to the RN102, I have checked both ends for a bottleneck and am unable to find any obvious bottlenecks. With the speed it is estimating that the backup will take 70 Hours by which time the backup will be out of date.
Is there any way that Acrosync can simultaneously send to several servers at once instead of one at a time? I will continue to see what I can do about the speed issue to try and find the bottleneck in the meantime.