Paying full months rent for 5 days of July?

My wife and I are moving. I was at retraining at Knox (which messed up, causing our movers to be delayed). My wife gave the apartment manager 60 days notice, and stated to her there might be a slight possibility of us staying a few days in July. Well, the movers cant come till July 5, and we are leaving the 18th to sign in (parents will be here for movers). Its a month to month rent lease now, and it does state full months rent for partial stay, but this manager never really enforces anything on the lease like loud music eviction. I know military orders can cancel a lease in Ohio, but what about this situation. We gave them plenty of notice, is there a military clause or something requiring them to prorate? Could my parents show them the moving orders to try to get out of a full month of rent, its a huge hle for so few days.