Own or not it's breaking and entering if the property is occupied, alot of landlords believe since they own the property it's ok to come in anytime that is INCORRECT and you can SUE and get alot of money for stuff like that. You can even stretch the truth and say you were naked as you just stepped out of the bathtub and the owner barged in, he has no proof that never happened and could get into very serious trouble.
On topic a lease is a lease if he signed a contract and his one month trial is out since you said you renewed a few months ago he can't do that, don't let them intimidate you conact an attorney if they persist and seek legal action I bet you they back down.