I'm hearing that VS are lining up a big A350XWB order to directly replace their B747s. If true this would also make a cancellation of the 787 order more likely. Virgin would have an all Airbus fleet.
It's not just the (ever increasing) delays on the 787 that are the issue. Range is also a factor.
Already much lower than first stated, if the fix for this "structural problem".. (which will probably result in adding Aluminium or Titanium to the airframe).. further increases weight and reduces range then the 787 truly becomes a dead duck.