Yongguk: if she woke him up from his sleep after working so late that night, and he probably would be, I think he would be honest with her and tell her that he’s extremely tired and that he promises to call her back tomorrow.
Himchan/Jongup: although he loves hearing the sound of your voice at any hour of the day or night, chances are he’ll probably sleep and not even realize that his phone was ringing.
Daehyun: he’ll be a bit groggy when he answers the call and will speak to her for a few minutes, 10 at most and then let her know that he’s going to have a busy day the next day and that he needs his rest, hoping she’ll understand that.
Youngjae: he’ll answer the call, but without realizing it was his girlfriend, he answers rudely. “Who’s calling me at this hour?” he says, his voice tired and when she apologizes his voice immediately softens and he apologizes for speaking so rudely to her. Chances are she’ll understand that she woke him up and they promise to call and text each other tomorrow.
Zelo: he’ll speak on the phone with her for a while, glad that she would seek him out when she felt lonely rather than going to anyone else. But during the call he starts getting sleepy again and tells her that he’ll call her again tomorrow because he’s really tired.