Open Question: After a year lease expires on a house how does a month to month lease work?

My lease which expired on 2/28/10 states that the tenant agrees to pay an 10% rent increase on a month to month basis after the term of the lease ends. I was told that after a lease expires it is to be either A) renewed, or B) terminated, or C) renewed with a month to month lease. SO, my original lease expired 2/28/10, and my property company expected the rental increase on my 3/1/10 rent, even though I have not received a new month to month lease agreement nor have I received a 30 day written notice of rent increase per arizona statute. Are they required to give me that 30 day notice or is my old expired lease still valid or did it become null & void on 2/28/10?