How does the ringing work during business hours?
When you turn on ringing services for night mode you are just making the incoming calls ring to what ever ext's are in the ring group you have set up in night mode. So if the lines are suppose to a ring 4 times at night i don’t think you need to use night service. You may want to look at the evening and nonbusiness timers in the voice mail system to make sure the correct greeting are set to play in those time slots.

If they are using night ringing too go directly to the AA you need to look at what ext's are setup in the ring group for night ringing. The voice mail DN's should be in the group and on other DN's

You don’t drown by falling in the water. You drown by staying there.