My court order says exacty that. My Ex gets to call the kids every single day that he doesn't have them at his house. He exercises that too by 8pm every day.
Does it bother you that he calls them? My ex has never really made it a habit to call everyday consistently when they were with me but the times he calls don't affect me because they are his children. I guess I have never walked in his shoes but I just don't see why 5 minutes is such a big deal. My issue with the time is due to him only giving me at 6 pm and not a block of time to make that call. If he said I had between 5-8 and they weren't available when I called it wouldn't be an issue but when HE gave me one specific time then it is up to him to make them available. I honestly would prefer the block method.