I think the article means 5 weekly flights to all destinations (eg MAN 2 weekly, DUB 1 weekly etc).
However, the article you mention is quite interesting that it states:
Jesus Almaguer Salazar , director of the Convention and Visitors
Bureau (CVB ) , reported that after some negotiations with airlines such as
British Airways , Virgin Atlantic , Condor and Thomas Cook , achieved the
opening of five new weekly flights from Manchester , Finland, Sweden, Poland , Italy and Dublin to Cancun , from the first half of 2014 .
This to me looks like the route is confirmed? We know TCX is for DUB, Condor is likely a TCX tie up for UK/DUB routes, so that could mean Virgin MAN-CUN is a done deal? (unless it is just poor translation but DUB is confirmed after all).
Also the 2 based B747 are fully used in summer (11 weekly MCO, 1 weekly BGI and 2 weekly LAS, so either CUN comes at the expense of another flight, or a new part based aircraft (perhaps 2 weekly MAN-CUN, 2 weekly GLA-MCO and 3 new LGW flights on 1 aircraft?)