I try to say Good morning to the controller and Good night to the controller via Skype every day and then we converse throughout the day as needed. She usually responds to the Good morning one, but she rarely responds to the good night one. I send it when it is 4:30 PM her time approximately. She's three hours ahead of me. I think she gets off around 5 or 5:30 though based on when I usually still get emails from her. I don't know if it is annoying her or she just doesn't think it is important but I say good morning and good night to the workers in my physical location so I think it is the same thing. But if I stop doing it all the sudden, she might find that strange too. So I don't know whether to keep saying it or just never end the conversation for the day....so weird. I tried to Google what the etiquette is on something like that but I can't seem to find the answer.