There are some answers we do have about the Rays plan to use four starters and mix in "bullpen days" when needed during at least the first six weeks.
They are not doing it because they don't have a capable fifth. Nor – for the Twitterverse smart alecks – that they can't afford one. And they didn't plan the "bullpen day" for Game 3 vs. Boston as a surrender, but actually a strategic move to ensure having fresh arms that day and providing extra rest going forward for No. 3 starter Nathan Eovaldi.
But the more important questions, starting with if it will work, and some of the specific hows, truly can't be answered yet.