they didn't really tell us the day and time for the PSO2 day changed either
It was a pretty noticeable part of their tweet about it:
The PSO2 Day: Premium User Appreciation Day is here, now under a new schedule!
Not really - They do the "It's PSO2 day!" every PSO2 day and so most users who have been playing wouldn't click on the article they posted. That twitter post was also specifically made hours after they posted the original article with little fanfare, because likely no one noticed (which was my point).
In any case, since it hasn't been fixed by now, I'm guessing there was just a communication breakdown somewhere and it is actually being extended. We'll probably get an announcement about it soon.