Bourton

They altered the way the window aperture was cut thus causing the stress fractures, AS have issued a technical bulletin about how it is to be repaired now, apparently the window is taken out ,the interior wall boards are removed the crack is fibreglassed from the inside and stronger wooden wall supports are fitted around the window opening to stop the flexing and new wall boards and and interior trim fitted. Talk on the Autosleeper farce book page indicates that this is supposed to have rectified the problem but only time will tell,  the other thing to note is that the outside will be filled and repainted to match, this will over the years discolour at a different rate than the Gel coat finish