What is the function of the USB port on the rear of the H1L-Series undefined units ?
Can these be used to add storage capacity using USB thumbdrives, if not can details be provided about what its purpose is ?
Good day. From the documentation I’ve been able to find, the H1L-series undefined does not support expandable storage. The USB port is intended as a power/charging output, rather than a storage port.
AOSU themselves have stated that compatible cameras can be connected directly to the HomeCortex for charging. So, as far as I understand it, the USB port was mainly provided as a convenient way to temporarily charge the cameras when needed.
I’ll admit, though, that if your cameras are mounted some distance away from the undefined, bringing the camera over just to charge it isn’t exactly the most convenient solution. 
If we look at it in a different way, perhaps you can charge other devices utilizing USB on there, which would make it a little more useful in practice
So what you’re saying is the USB C port and this USB A/B port meant to be used for charging the camera ?