Both MacRumors and AppleInsider are reporting on an analyst report that Apple may update almost every major piece of hardware in the next six months. In addition to MacBook speed updates, there may be a new MacBook Air or a new low-cost model to replace it. The iMac may get a significant update and even the Mac mini as well. A whole new line of iPhones, some with OLED displays and all with Face ID and A12 processors. Also perhaps a new iPad Pro with Face ID and no Home button. And last but not least, a new Apple Watch with a larger display and new health features.
It is important to remember that analysts are just guessing. They are educated guesses based on monitoring lots of data like supply lines and such. But still, they are hardly ever 100 percent right, and very often mostly wrong. But this seems pretty reasonable.
We can probably expect the bulk of these updates during two announcements, going from how Apple has behaved in previous years. There will probably be one at the end of September to announce the official release of iOS 12, new iPhones and new iPads. Then perhaps two weeks later a Mac announcement with macOS Mojave, and new Mac models.