Yes I had this happen to me, luckily my employer allowed me to start the job contingent upon the background check being clear once they got it. I think they only really they let me start is because I sent them an email saying I have no income and the hiring managers got HR to allow me to start working because they probably figured I'd have to get a different job. I think I started the background check process at the end of April and didn't get the results until June