So in the long run, this question of Scotus has nothing to do with Sabbath-Sunday debates (which turn on Church authority and very early church history, anway) currently played out among those who dialogue with groups such as the Seventh-Day Adventists.
In other news, while reading a question on the connection of the moral virtues, Scotus repeated the traditional claim that virtues can only be formed by repeated acts consonant with right reason. His "voluntarism" is of an entirely different nature than the Cambridge phantasists and Fr. Schall deign to report.
Ordinatio III d. 37 q. un. n. 21:
"The third precept of the first table, which is of observing the sabbath, is affirmative as far as to showing some worship to God at a determinate time; but as far as to the determination of this time or that, it is not part of the law of nature strictly speaking. Likewise, neither is it of the law of nature strictly speaking asf ar as to the other part, the negative, which is included there, by which a servile act is prohibited, for a determinate act, prohibiting one from then showing worship to God: for that act is not prohibted unless because it is impeding or holding back from that worship which is commanded.
n. 24: if however this third commandment is not of the law of nature strictly, then it should be judged about it, with respect to this, just as of the commandments of the second table."