A chance yes, though my guess is still WWDC. A May launch for the iPhone SE 2 (if the rumors are right) would be plausible because it would take one more hardware announcement off WWDC to leave more room for everything else, and the SE 2 would "only" be the low-budget iPhone option anyway and not have the newest cutting-edge technology (iPhone 7 specs, no Force Touch and so on). It would be a "less exciting" product (at least on a technical level), so it would make sense for Apple to release it separate from WWDC.So with the news of a possible iPhone SE update next month, May, there looks to be a chance of a refresh of the MacBook Pro around the same time? Several device makers will be launching products then and it would give Apple time to announce and make available a product within a few days.
Macs on the other hand have been released at WWDC for the last couple years now, in fact it seems as if Apple wants to bundle their release around WWDC if the release windows allow it. Last WWDC had new MBs, MBPs, iMacs and the iMac Pro announcement; that's a lot of news in terms of new Mac hardware. With how big an exciting of a leap the two additional cores are, it would make sense if Apple wanted to talk about it a little at the event – after all, the WWDC is a developer-focused event and the new chips are big news for developers aswell.