I depend on scheduled DND on my iphone to let me sleep without noises, vibrations, or light coming from my phone in the middle of the night. it keeps me (and my wife) sleeping soundly when the phones are charged in the bedroom. regular DND it's a life-saver in a meeting.
but more than that, it's a feature i PAID for. for all of the "it just works" messaging that apple marketing loves to spew, it sure does get a lot of date and time bugs that should NEVER make it out of QC. if one of my customers had to deal with this bug in our software and i said, "don't worry about it, the problem will resolve itself in a couple of days, just don't use that feature" we would be fired on the spot.
if it's a free service, then i can accept a hiccup like this. i know that issuing a software patch might take a few days, and i can be pissed off while accepting that. but that isn't the message, it's "we know about it, it will get fixed automatically after this date, so just live with it" isn't an acceptable response to a bug in a product i PAID for.
maybe you have a lower threshold for quality in what you pay for. i don't.