I show no such update when accessing standard Windows Update on my Surface Pro 3. Goes off to look at the Microsoft Update Catalog... doesn't come up in search there either (and I can't get the catalog search to work either on IE or Edge, but comes up fine in Chrome -- go figure!) Thus, for example, here's what comes up for the first item in the preceding list:

Perhaps the update hasn't yet made it into the catalog? I'll keep checking WU and the catalog going forward...
Thanks!
--Ed--

PS: I'm an idiot: I didn't see this was only for Windows 10 S, and mistakenly assumed it was for Windows 10 in general. I guess it won't be showing up for mainstream Win10, then. My bad!

Hey Ed, :)

These are only available for the "Surface Pro (New)" devices, and not for any other Surface devices. "Surface Pro 3" devices wouldn't be included.

Microsoft Surface update history | Surface firmware updates

Thanks Brink: I already disqualified my Surface (Pro 3) because of the Windows 10 S connection. But thanks for pointing that out as well. Much-appreciated.
--Ed--