If BA do park aircraft, and some of them are LHR based, presumably they could glean some revenue from leasing out the slots or even wet lease aircraft and slots combos to other operators (Maybe they could flog a 75 and LHR slots to the good folks in the Shannon region!)
Dose LHR operate a "Use 'em or Lose 'em" policy on slots, if so, how many do you need to miss before they get taken away from you?
JAS