I understand what you're trying to say, but in the business world delays without explanation are never acceptable. I'm an IT project manager, so I understand very acutely how the business world deals with delays.
If an electrician rang you and said he was coming out on Friday and never turned up or rang you and then two weeks later rang you up out of the blue and said "oh I'm coming out today instead", what would you say??
Delays are fine (within reason), as long as you communicate them and keep the stakeholders in the loop.
Again, under promise, over deliver. In the Ann, why didn't they say the App will be out by the end of June and then deliver it early. Better than saying it will be out in 3 days and then releasing it in 13 days without any communication whatsoever.