Not sure that this is as it appears! When you use the option under windows to “make available offline” you are creating a cached copy of the “offline files” on your PCs hard disk - it’s in the CSC folder under windows. Windows then does background replication to synchronise changes between the two drives over a period of time. The network copy speeds that you are seeing when copying from your PC to the network folder may actually be the speed of copying to the CSC folder on the same PC.
Out of interest, I’ve just tried copying a 20MB file to & from my live hub and am getting speeds of 43MB Write and 37MB Read on latest firmware. Caching on the hub could explain why write is faster than read! Nothing special about my network, cheap and cheerful 100MB
