The 2 Week Notice

Hi all. Due to unforeseen circumstances, unfortunately we are having to disrupt and move our first placement after only a couple weeks. My question is, what is your experience with the 2 week notice of intent you give the agency to find a new placement? Do they almost always take the entire 2 weeks? Is it possible for it to only take a few days, a week? Can they go over those 2 weeks, or do they find respite if it's over 2 weeks? If I need FS out of my home this week, what are my options? Thanks in advance.