Update:
I've holding the shipment in Shenzhen as the inspection by my forwarder highlighted some potential problems, specifically a few boards with the wrong build options (some bits missing which shouldn't be).
They have been returned to the assembly plant on Friday for a full audit.
Depending on my confidence level,I will release them tomorrow - or they will have to wait another week until I arrive in China and inspect them.
The freight is very expensive (hundreds of USD) + import tax and VAT etc. I don't want to have to send them back again.
This first large-ish batch is to get the process in place for full production, so I need to be a little cautious otherwise there will not be enough funds to make the next batch

I'll update you as I find out more.
/MikeJ