errr....
not quite accurate polly because ( up till now and please dont let it start ) mia is not involved in any of our rostered back to backs
a back to back usually only involves east coast states/ canada for ba crews. ( and that according to ba includes ord and dtw )
it involves four transatlantic sectors in as little as five days
e.g
lhr-jfk night stop
jfk-lhr night stop
lhr-iad night stop
iad-lhr
they can be as little as five days for some bostons and washington dc's, where the layover is barely more than 12 hours or up to an 8 day trip where the itinery is as follows
lhr-jfk
jfk-lhr
lhr-ord
ord-iah-ord
ord-lhr