The company has said that officers may bid for any vacancies in their base area. However, there are, at present, no vacancies so it's HKG or bust. Cargo guys with families will find that really tough and commuting only a short term fix.
IMO Man will not be closed but numbers reduced to cover the service only there are plenty of 744 drivers in LHR. As most of the MAN base is ex KA I don't think CX or many others will care that much, we'll have bigger fish to fry.
This is another Pole Shift moment, and remember, that the base review is still ongoing, that is stated in the letter. So another threat left to linger.