Choir rehearsal

I used to be in a church choir and I do know how frustrating it is that people drag in late and rehearsal starts late. However, an hour late is ridiculous. Most church choir members have been in that same choir for several years and are bored and they feel they know the songs well and don't need to rehearse and become less motivated all the time. Something needs to be done to get things back in control so that you can begin promptly at 7:00 and be out of there by 8:00! Perhaps your choir director has lost motivation. If he/she would start promptly at 7:00 no matter if everyone is there or not, then eventually, the tardy ones might begin to make an effort to be on time. After all, they know it never starts on time now, so why hurry?