They are in the Workforce Strategy FAQs through MyHR. The radius is 30 miles. Employees who are remote right now, even if they were hired as a remote worker, and live within 30 miles of a HUB will be required to go in 3 days a week. Remote employees who do not live in a HUB or are 30+ miles away will remain remote. What is unclear is what happens to people who are hybrid but live outside of the 30-mile radius.
Bumping this for info from @8uoh+1rbdtfhh.
If you’re coded as hybrid and you live outside of the 30 mile radius the expectation is for you to be in the office three days a week. You’re manager just never enforced it.
I think that they could arbitrarily change the mileage. Depending on the hub, a 30 mile commute could mean 1.5 hours one way in traffic. I am remote and I am 33 miles from a hub, but that won't stop them from forcing workers to come in, or changing the goal posts with the distance.