Apparently Passan said that Skenes could be up in May. There's a world where it happens, but I'll believe it when I see it honestly. The Pirates are not going to run the risk that he could earn a full year of service under any circumstance, but in principle it's possible that he comes up in mid-May or so, is solid but has some bumps, and then is sent back to AAA around the ASB to manage innings and also to give a shot at being super two ineligible, and then back up a few weeks after to rejoin the rotation.
In that scenario, I think he likely doesn't have enough momentum to take one of the ROY spots. There's always a possibility that he is so electric from the very start that he runs away with the award and makes it impossible to even think about sending him down, but it's too many ifs and buts right now. If that scenario emerges and the Pirates are decent enough in these early 6 weeks, then you are perhaps talking about Skenes leading the Pirates to a division W. I think that's the only scenario where they might be fine chucking the service time game out the window, but it's extremely improbable.
The major thing that is giving me pause in terms of pessimism is that he is starting in AAA. We'll see what kind of management he's on, but they sort of have to put him on a 5-day schedule given what they've said. That's not always the case in the minors, though I guess it often is for AAA pitchers given that they are your emergency reservoir for MLB. In any case, I think they could buy themselves a slight bit of time if they have Skenes out there for a couple of 4 IP type starts, but to be a betting man about it, I really just don't see a scenario where he picks up extreme momentum for a call-up before the calendar says May 1.