If it's a new roof then the monkeys who originally installed the roof would be required to come back and hit it some more with their mallets. That's why raindrops keep falling on your head. The drywall professionals will wait for the roofing anomalies to be rectified. The owner/owners insurance company wouldn't want to keep on paying the drywall people (We charge like wounded bulls!
) to come back and repair the water damaged ceiling every time it rains. Carpet can be dried out if it's not too far gone. There's a whole lot more I can tell you about the building game, but I'd have to kill you if I did.
Is your ceiling - or what's left of it - a "set" ceiling (ie. plasterboard/drywall or whatever you call it in America) or a metal grid with drop in tiles?