My guess:
It'll be situational. In mop up play, probably Stidham, just for experience.
If the game is close, Hoyer, to manage it without mistakes.
It'll be a while, probably into next year, before Stidham gets meaningful snaps in the regular season. There is an order of magnitude difference in the processing speed requirements between what he saw last night (non starters, playing vanilla) vs. regular season (starters, playing disguised coverages and rushes).