Do not count on this idea that returns won't be changed or at least won't be changed within 30 days of the trip. My change was what I believe most folks would consider a serious change, and it came today, 11 days from my departure. By serious change, I mean that my RETURN flight had been changed to leave on a different (following) day, without any email notification going to me. Not a bother to me as a leisure traveler but it could be more of a problem for someone else. Also, if I had not known, I would have wasted a trip to the IST airport on the wrong morning and then had to leave and come back. As it's more expensive to travel there before 6 AM, it would have been an unneeded nuisance and expense not to know ahead of time.

I do get email notifications of the constant Delta changes of time, every time they change a flight by 5 minutes they send an email, but this particular change involved the KLM portion of the journey. Delta was not aware that they also needed to change their portion of the trip, until NW informed them at my request. It popped up fixed on delta.com maybe 30 minutes after I called the NW Elite line to ask why delta.com still showed me leaving ATL-MSY on April 1 instead of the next day.

I've come not to expect anything except the unexpected, frankly.