Who knows? The way the market has been for the past few years, it's probably well too early to even consider. Teams will have to begin to wave the white flag, but with how April shook out; if you're in the AL, your record probably sucks but so does everyone else's. In the NL, your record is probably over .500...but so is everyone else's.
Cubs should have ammo, but as they made it clear last year, the prices were expensive and they were unwilling to make the kind of commitment others wanted for top arms. So I think any addition will be smaller than larger.
If there's a positive, in theory the Cubs could be just fine. A playoff rotation of Cabrera, Boyd, and Shota is fine and while the Steele injury isn't great news or anything, it's not so bad that we have to cancel his season yet. You add him to that and that's a good four arms. You're missing a "playoff ace" but maybe you make up for it with four strong arms and a bullpen. They definitely need a BP arm or two but hey, they're pretty cheap comparative.
(the down side is that the way the season has gone, expecting those four to make it to the finish line feels like a longshot, but I guess at some point, you'd think they'd stop all being broken)