Seems perfectly reasonable to me, albeit I'm not a left wing pinko, for the flights to take place
with cargo but without passengers because of a lack of cabin crew.
Hundreds of flights a day operate with cargo but without passengers because that is their line of business.... BA would be silly bumping the cargo onto another flight (more likely flights plural) because these other flights would pobably already have their, if not full then nearly full, quota of cargo.
So if the journalists really feel a need to report on this, surely the real (non) 'story' should have been
'BA unable to man all scheduled flights due to lack of manpower/poor planning/staff cutbacks/illness' (delete or insert another reason as applicable) or
'BA fulfill their commitment to transport cargo to the States despite lack of CC'.
However we have ended up with another easy to write, unresearched story jumping on the popular bandwagon of 'lets decry aviation as
the major planet killing mode of transport'