British Airways (London) is taking each of its eight Boeing 787-8 Dreamliners out of service one at a time for routine warranty service work by Boeing at Victorville, California. Starting with the pictured Boeing 787-8 G-ZBJA (msn 38609), each aircraft from the first four deliveries (JA-JD), is expected to take around 10 days for the service work. The last four 787s to be delivered (JE-JH) are expected to take less time since they are closer to the new 787s being delivered. Each of the eight aircraft, when finished, will be the same as new production 787s currently being delivered. This is normal procedure for a new aircraft type as the manufacturer often makes some changes as aircraft roll off the production line.
Copyright Photo: SPA/AirlinersGallery.com. G-ZBJA departs from London (Heathrow).
British Airways: 
This news is over a month old. The primary reason is the flight deck windows are not correctly fitted amongst other things. The third aircraft goes out in a few days
Thank you Jon for the additional information. All the best.
Bruce