S.G.
I also think that it's "all of the above". Any change in routine can create temporary behavior "issues" in children that age. But I think the biggest factor playing a role in this situation is that she's going to be 2. My 1st son is 28 months and can be quite a pill at times. And there are usually no other attributable factors that can explain his behavior. So at that point I chalk it up to him just being 2.
This may or may not help, but I wanted to offer that I've been there and I'm still going through it. Also, I live in Alameda, so feel free to message me if you want to connect.