This post is filled with assumptions. In aviation, the specs generally come down from the OEMs like Boeing or Airbus, who have systems engineers who've done a l

This post is filled with assumptions. In aviation, the specs generally come down from the OEMs like Boeing or Airbus, who have systems engineers who've done a lot of work creating the specs and defining the nuances. Granted, there are errors (and external bosses who push requirements), but when they are seen down the line by a supplier, they get raised and discussed with the systems engineers at the OEM. Generally, these specs are pretty tight and specific. For something like this, the OEM probably had the operating time set to something like 25 days (over 3 weeks of never turning the plane off once), which gives the timer plenty of room. However, if the customer then doesn't restart for more than 6 weeks, and that's outside of the OEM's specs for the plane, then you're going to have issues no matter what. The actual larger cost is not the maintenance or updates but the verification. There are definitely issues, especially when it's a code base you've been maintaining for 15-20 years, but generally it's the verification that takes the most effort, since often you're not just verifying the new functionality but downstream functionality as well.