The data files are
probably not under copyright because they are simply a compilation of facts,
like a phone book.
The program itself is, though.
That said, the larger question to me is this: if you uploaded them to github, you would likely have only the major routes updated. Updating these files is a daunting task without any sort of automation. Even if you had a everyone who reads this thread doing it, how long would it take to cover even the largest airlines? For instance, the
American Airlines timetable is a 36 MB, 1131 page PDF. The routes.dat file itself is 72408 lines in the latest version.
So the question for me is how cockpitvisit compiled the data in the first place. If he was doing it by hand, then I certainly understand why he has not had time to continue updating it! Even if the task were partially automated, it could still be pretty laborious.