Sorry, I just can't justify being upset at Disney for making a change that alters an unofficial perk of an early ADR...had Disney included "come early to be alone in New Fantasyland" or "See Main Street with nobody on it" in the breakfast descriptions for CRT, then sure you would have a gripe. But what they did was assess their hours and it altered a secret tip some people enjoy using...happens all the time and again, it is just like when we found out HM was closed most of our trip...we jokingly said, "let's cancel!" but wouldn't go so far as to calling it having upset our apple cart...maybe we lost one apple, maybe you lost two if you want to count being ahead of the RD crowd...but that's about it...but they left you an orange in its place, additional park hours
If you notice, they DID add hours on at the end since the 180 days past...so you got your wish for later hours too.
Why didn't they set these dates at 180? Well, perhaps they weren't certain about the crowds...or once they were, maybe the logistics of staffing and other facilities required a more recent decision.
BUT...if you fault them from not expecting the need, having seen that they have changed openings like this for a few years now, aren't you falling victim to the same charge of "should have seen it coming?" Sure this is the earliest to date that they have done this, but people have been saying the crowds are getting bigger earlier every year.
What they did is a benefit to more than 99% of the people going to the park those dates...and it isn't a tangible harm to the other less than 1% so pretty much is a no-brainer win-win.