Sorry to bring this back up - but I'm still having problems

I have 3 offices. Their front desk extensions are:

x3000 (central office)
x3500 (branch 1)
x6100 (branch 2)

During weekends, there may or may not be someone at x3000 but there may be at x3500 or x6100. These people at x3500 need to remotely disable night at x3000 so calls made to that office forward to them at x3500 or x6100. Right now someone has to physically walk into the office at x3000 to disable night. Once night is disabled the people can easily forward calls from x3000 to either x6100 or x3500 using remote programming.

Is there any way to disable night from one of these remote branches? If not, in DB programming (axxess 10.0), where can I specify for night to automatically turn OFF at a set hour?

Thank you for all your help!