> You are bound by their conditions of carriage when it comes to schedule changes and the time change period they will permit you to change dates or get a refund.

Yes, that's a general statement and usually a change fee can override it. Now I have to lose the entire ticket because of a change they made.
What's a significant change is also not clear - I've heard less than 4 hours/2 hours/1 hour from the airline's reps. If it's written down somewhere, their reps certainly don't seem to know about it.

I'm still hoping that they'll cut me some slack since they changed what was supposed to be non-changeable and the flight is a month out.
Also, I don't see the category name "non-changeable" defined anywhere. They should spell out exceptions to this category or define that non-changeable really means "you can't change it but we can change it whenever we want".