Originally Posted by
CPH-Flyer
Since Zürich does the refurbishment and MLA the heavy MRO, I don't think either happen at the same time. So I think the 4 months is just a coincidence of the two schedules falling pretty close. Once the refurbishment is over that down time is out of the fleet for some years to come.
As far as I know Zürich does both, and the refurbishment is just 1 of the 4 weeks if any, as they more or less strip the birds to their bare bone during the heavy checks anyway.