The valve problem is not a software issue but reportedly is definitely environmentally related, the result of corrosion from moisture combined with slight seal seepage of the dinitrogen tetroxide oxidizer the valves control. And unfortunately, the moisture was not simply the result of abnormal rain intrusion as first suspected, so is not a quick-fix, think valve redesign or different valve coupled with wholesale replacement. Seems as if without bad luck Boeing would have none at all.