I mean, when you OPS 1.1 even in only 50 PAs it does affect your projections a little bit. Assuming the Orioles really believe in the quality of contact and strikeout rates etc. then it would meaningfully affect his projections. Mookie Betts has already added 1.7 WAR from his preseason ZIPS projections, while Hays has lost around 1 WAR.
I initially guessed when he was sent down that if he continued to rake that they'd bring him up before the 15 day cutoff, because it would meaningfully change his projections enough that they'd be likely to lose the extra year anyway, and they would want to give him the opportunity to earn an extra pick.