Thats why it is an unexpected delay, it was..unexpected!
They announced 1.1 fully believing it would be ready within a short time, they did not realise there would be a delay, so even if they did "announce 2 weeks before" as you suggest, had they hit an issue, then that 2 weeks might have turned into months.
They announced 1.1 fully believing it would be ready within a short time, they did not realise there would be a delay, so even if they did "announce 2 weeks before" as you suggest, had they hit an issue, then that 2 weeks might have turned into months.