Whoa. You cannot cite this guy as an authority, and then ditch him when he starts to be inconvenient to you.
You picked him as your authority for your assertion that the ECF were Sabbatarians. Now you gotta stick with him.
I picked the guy because he is the guy who started the switch. This document can mean nothing except "Quit keeping the Sabbath and move to Sunday". Why else would he write such a paper? Good grief, dude. He makes up Sabbath worship right here. It is plain. There is no scripture that says "Thou shalt keep the 8th day in honor of the new post mil. Heaven". It does not exist. The 62 quotes I pasted above say the same thing. Sunday is not Biblical - it is an invention of man.