Deadline due!

I've got a deadline due in two weeks for an assignment that I've been working for over a month. And guess what?? At today's meeting, my boss tells me that they are changing the specs. What does this mean for me? My one month worth of work goes down the drain and I have to redo the design again with two weeks left. Hmmm.....have you ever found yourself in this kind of situation before? What do you do?
First, I need to b**ch about it first. Once that's out of my system, then I can think clearly and start evaluating if the change in specs makes sense or if it's impossible to meet. Sometimes, as designers, you can't just take whatever management throws at you. If it's not possible to meet that specs based on the limitation of the technology or for whatever reasons, we must sound it to them.
Then, I would assess the amount of work involved and the required time to make those changes. If I find that I do need more time to implement the changes, then I'll need to talk to my boss to extend my deadline.
However, management should be pro-active in defining the specs early on and not just push designers to jump start on the design asap so we can rush for the deadline. Decisions on the specs and what kind of devices are we using for the design should all be defined early on in the project before we start designing. It is more efficient this way. Of course, along the way, there is always specs changes but at least they are not major ones. However, most of the time, we are always designing without the specs well-defined. It's all part of the process.
Anyways.....after all this b**ching about it, I realised that it's not much work after all, changing my design. Haha....the specs have been relaxed, which makes it easier for me and there are no major disruption. I'm still able to meet my 2 weeks deadline. Woohoo!