I just learned from Bitsyncom that tracking numbers aren't generated until they leave mainland China [i.e. Customs]. Then it is handed off to DHL which then generates the tracking number.
That is how it works when you use an HK forwarder...
Perhaps that is the company they contracted to take care of the shipping paperwork. Customs broker of some kind or a Forwarder.
Might explain why they are sending shipment in clumps instead of FIFO.