Diesel8
you may or may not know that LHR is a saturated airport. Well, it is. To give ANY carrier preferential treatment would be unfair. You may also recollect that BA (and others) are in LHR since a very long time, therefore having grandfather rights to slots (but not to new ones). You want to come, show you have traffic rights and queue up, like everybody else.
Why in Gods name should any US carrier get any form of preferential treatment?