I don't know if there is an automatic answer to either of those questions. Even if there is, how is it reasonable to equate that to not making it back on indoc weekend under otherwise reasonable circumstances?

If someone planned on one flight that got them back 20 minutes before class started and it was delayed or cancelled, OK that's kind of dumb. How about 2 flights that get back the day before but all the stars aligned and they were both suddenly cancelled, and they called as soon as they could to give the company a heads up? They will be fired for that?

That's not only unreasonable but also seems very unlikely they would even think of trying to do that.