Excluding the usual marketing speak no information on when it is going to happen is available:
https://www.zdnet.com/article/what-happens-to-your-g-suite-unlimited-storage-when-google-moves-you-to-workspace/
The question therefore is... does anyone have the timeline? Is anyone pre-paying for the 1 year license to buy ourselves 1 year migration timeline? Anyone heard if we would be allowed to pre-pay for another year if there's an announcement of the deadlines? Has anyone been approached by that special team for their customized transition?
And if you happen to work for Google you should realize should you make your G Suite customers unhappy with how this transition is handled, you may as well stick a fork into any CGP aspirations Google's management has.