A news story out of the Diocese of Fairbanks in Alaska describes an upcoming "priestless Sunday" wherein priests will be away from their parishes to serve remote missions, leaving their parishioners without Sunday Mass that weekend. I can see arguments for and against this unusual action and I don't think that outsiders are in a position to conclusively support or reject the basic idea.
One point in the news article, however, needs to be corrected: After noting that Communion services will be celebrated in most parishes left without pastors, the article asserts that such services are "not Mass but will satisfy the Catholic obligation to attend Mass."
Only Mass satisfies the Sunday obligation (1983 CIC 1247-1248) under Roman Catholic canon law.* If a member of the faithful cannot attend Mass on Sunday, that impossibility excuses the obligation. Boniface VIII, De Regulis Iuris, no. 8, "Nemo potest ad impossibile obligari." Indeed, Canon 1248.2 of the 1983 Code, placed in the Code by John Paul II himself (Peters, Incrementa in Progressu, 1082), expressly notes that "If participation in the Eucharistic celebration becomes impossible because of the absence of a sacred minister . . . it is strongly recommended that the faithful take part in a liturgy of the Word if such a liturgy is celebrated in a parish church . . . " (emphasis added). Note, participation in a Word service is recommended, not required, and there is nothing in the canon about Word celebrations counting as Eucharistic celebrations.
Those of us lucky enough to attend Mass in our own parishes next Sunday should especially remember Catholics in Alaska who are not so fortunate. That said, while severe shortages of priests should move us to redouble our efforts to encourage vocations to the priesthood, they are not occasions for changing the understanding of Sunday Mass or its obligation.
* I say under Roman canon law, because there is some provision under Eastern canon law for something besides Mass to count toward the Sunday obligation. See CCEO 881.1.
I am sure that there are other canon lawyers that would argue differently, but this has been my understanding with the limited canon law courses I received in the seminary.