Since you can fly the 787 without an APU battery or APU, we're honestly saying that because one Ship's Battery failed in flight we should therefore determine the 787 is no longer suitable for ETOPS-180?
Should we find the 767, 777 and A330 not suitable for ETOPS-180 every time one of them suffers an inflight shutdown of an engine?
Should we risk finding the A350 suitable for ETOPS-180 before EIS? Or should it suffer an IFSD or some other ETOPS-related systems failure, should we immediately find it unsuitable?