Hi, hoping someone can help. I have 2 extensions on my Avaya system set up as operators. Our main line 7800 and a second extension in my office 7830. I want to change 7830 to another extension 7856. Working with a 4424LD+ phone. I have been looking for awhile to try and find instructions and have been unable to locate anything that helps. Would really appreciate any help you can offer.