Just for anyone else finding it a bit difficult to follow, the BA A380 was instructed to taxi on November and then should have turned left onto Mike (parallel with both 22 runways) but didn't and then crossed the displaced threshold of runway 22R without clearance, mistakenly continuing on November until it reached an area of the taxiway under construction.

No comment on why it may have happened but taxiing around a huge A380 in a potentially unfamiliar airport (not sure how often the average BA A380 pilot visits BOS) must be a difficult job at the best of times.