Hi this is Scott McArthur and I just wanted to call attention to a blog that I worked on with some of our PFE engineers that just posted related to Surface.
How to Update the Surface Pro 3 Firmware Offline using a USB Drive
This blog shows you how you can update firmware from a Bootable WindowsPE USB flash drive. This is useful for some scenarios where you need updated firmware BEFORE you do a deployment to the device. Hope it helps with your Surface deployments
Senior Support Escalation Engineer