Software Update restarts during re-maging with Sierra

Valued Contributor

I use Casper Imaging to re-image Macs with Sierra image; use the same tested process as with El Capitan, but Mac keeps rebooting. Log shows that Software Update somehow interupts everything and reboots Mac.

FINAL System shutdown message from _softwareupdate@LC02QN2NHGCN3

System going down IMMEDIATELY

It happens only with new MacBooks with one UCS-C port. Might it be related to "USB-C Multiport Adapter Update 1.0"?

Any advise or guidance would be greatly appreciated!