While the buzz leading up to Apple’s Worldwide Developers Conference is mostly about the Reality Pro headset, Apple could make a few Mac announcements that will be very interesting. In a tweet this past weekend, Bloomberg’s Mark Gurman wrote that Apple is starting trade-ins of some Macs currently unavailable from the program starting Monday.

As Gurman reports, “Apple will start accepting trade-ins of the Mac Studio, 13-inch M2 MacBook Air and 13-inch M2 MacBook Pro on June 5th.” That is a strong indicator that there will be new models that existing users might want to upgrade to.

I have on hand a 13-inch M2 MacBook Pro and tried to see its value in Apple’s trade-in program, but the value indicator did not allow me to select the proper release year (2022) for it, which prevents me from getting a trade-in value. That implies that I can’t trade it in. (I don’t have the 13-inch M2 MacBook Air or Mac Studio.) It’s possible that on June 5, the trade-in values for these Mac models will be added to Apple’s site and customers can see how much Apple could offer during a new Mac purchase.

This leads us to the next part of Gurman’s tweet where he said, “Read into that as you will. I’m expecting new Macs at WWDC.” The link Gurman provides in the tweet is not for the most recent edition of his Power On newsletter (which doesn’t mention the Macs), but for the April 16 edition, where he reported on new laptops being announced at WWDC.

While Gurman’s tweet can lead people to think that Apple will release a new 13-inch MacBook Air, 13-inch MacBook Pro, and Mac Studio at WWDC, it may not necessarily be that straightforward. It’s long been rumored that Apple will release a 15-inch MacBook Air, a new addition to the Mac laptop lineup, and customers may want to trade in a 13-inch laptop for the new Air. The Mac Pro (the last Mac to transition to Apple silicon), is the type of model that Apple would debut at WWDC. It’s a high-end Mac for professionals and could offer a significant performance boost over the Mac Studio–so much so that current Mac Studio owners will want to trade it in for a Mac Pro.

So, add in the macOS updates, and WWDC could end up being a significant one for Mac users. Apple’s WWDC keynote is on June 5 at 10 a.m. PT. Here’s what you need to know about WWDC, as well as how to watch the keynote.