MicrosoftStephen,
We fully understand the concept of phased deployment. That is exactly what we are trying to accomplish using your own documentation and the configuration options built into Windows 10, GPOs/ADMX, etc.
You can't tell us to not let the terminology get in the way when that terminology is literally the basis of how we configure phased deployments based on your own documentation, GPOs, and settings in Windows 10.
In fact, 1803 still has the configurable option of Semi-Annual Channel and Semi-Annual Channel (Targeted). If these terms are out of date or no longer relevant, why are they still present in the latest release of Windows 10?
Windows 10 is configured as SAC(T) by default. Individuals or enterprises change their update channels to SAC in order to defer or avoid unexpected Feature Updates on those systems before testing it (i.e. phased deployment). By releasing 1803 directly to SAC, those computers will actually receive 1803 BEFORE everyone else, BEFORE having the opportunity to test.
EDIT: After testing on a Win10 1709 VM without GPOs applied, it seems that SAC(T) and SAC configurations work as originally intended per your documentation (as of today 5/3/2018). When set to SAC, it only downloads the latest 1709 quality update. When set to SAC(T) it downloads the 1803 feature update.
Your release information document should be updated to more accurately reflect this: https://www.microsoft.com/en-us/itpro/windows-10/release-information
I think there may be confusion as to what declaring a new Feature Update as "Semi-Annual Channel" actually means to Microsoft versus everyone else. Are you only referring to the beginning of the 18-24 month support period? Or are you referring to the distribution via that update channel? Or both? Right now they don't seem to line up.
