I have 8 windows clients and 1 linux, but so far have only checked 4 of the windows clients. Looking at my graph I believe at least one other to be hung.
2 of the 4 halted yesterday at 16:06 and 16:24 Mountain Time yesterday. These times are appoximate times based on the log and the fact I beleive they hung submitting a finished block. Interestingly, I had a client (on the same network as the 16:06) successfully post at 16:13.
It seems that the server is the problem. As the two clients were across town from each other their Internet connection is hard to blame (although they both have the same DNS server). Also looking at a few graphs at SoB several Teams have had sharp drop-offs at that same time.
One client showed 100% block completion and the other 99.9% block completion. Neither had an entry in the log for that block. When I exited and restarted, one restarted the block at 93% and the other at 56%. I find it strange that the cache was not updated as I exited.