Howard Oakley, on eclecticlight.co:
Later this year, we should expect M2 Mac minis and iMacs, most probably around October-November. It looks unlikely that the Pro and Max versions of the M2 will be available in production quantities this year, but might be released in 14 and 16-inch MacBook Pros as early as late Spring 2023. That leaves the high-end Studio with its M2 Ultra for July or September 2023 at the earliest, and possibly as late as November, ready for the M3 to be announced at WWDC in June 2024.
Best informed speculations you’ll likely find. I’m using it to manage my expectations.