Over on the CAA website you'll find this:docs/5/ergdocs/ba_stanfeb07.pdf
'Extending the current Price Control on Stansted Airport - a Consultation' Response by British Airways (BA) plc
In paragraph 11 you will find BA's current thoughts on Manston . . . .
While some limited alternatives do exist [to Stansted], these are either substantially further away (e.g East Midlands, Manchester) and/or currently have inadequate facilities (e.g. Manston has inadequate security provision and other facilites while Luton has an insufficiently long runway for 747 Freighter operations; etc etc etc . . .
Somehow, I don't think we'll be seeing BA Cargo in Manston for a while!