EB1 to EB2?

[ConfusedHusband]

Hi! My wife has been working here in the US for around 4 years now. She has worked in our home country for more than 2 years. Her employer has filed for her green card petition (under EB1) and was already approved. However because of the backlog, we still have to wait for another 3 1/2 year before it becomes current. My question is if she quits her current company and have another company file for her green card petition, can she be filed under EB2 since she has accumulated more than 5 years experience already? Do they count US experience in the 5 years?

Thanks in advance.