From the Greenline website.
For your return journey, you will go to stop 12 and the shuttle bus will connect you again with the coach to London.
Our staff will be on site to ensure a swift and easy transfer.
Actually I did not see anyone from Greenline at the airport today directing passengers. Maybe they have been banned from the CTA? All the Greenline signage has been removed and National Express are now using the old Greenline bus stops. Four National Express employees in yellow jackets were mopping up any potential Greenline passengers although there was a queue by the coach stop in the drop off zone for the shuttle bus to the new Greenline start point.