Hi Russ
Welcome to the crazy world of NATS. Yes, you are correct that short notice is the norm for just about everything. In fact, your notice was almost a month, so that is almost unbelievably long-term planning. No undue cynicism intended, it has always been par for the course. Many of us can recall finding our posting notice to another unit waiting for us when we eventually arrived there !!!
Don't worry unduly, just go with the flow.
Good luck!!!!