I stand to be corrected but I understand the limiting factor is the aggregate frequency limit of 31 per week for each country, to all destinations added together. There is also a limit of 6 cities per country, but I guess that isn't of immediate concern.
HKG and (I assume) Macao are covered by separate agreements and do not therefore count towards the frequency limit.
Regional UK airports (sorry Bagso) are not treated separately from London, so if China wants to operate 31 weekly services from London then there isn't the headroom to fly from MAN or elsewhere. But is a China approaching this limit - if not, then the bilateral can't really be blamed for the lack of MAN services?
Does anyone have any updated info?
See also
http://www.aviationeconomics.com/New...rease-flights-