Many years ago legal holidays were off-peak but not anymore.
I took a look at the VZW site and couldn't find where they are specific about it. Only the times are listed...
Night Hours: (M-F) 9:01 p.m.-5:59 a.m.
Weekend Hours: 12:00 a.m. Sat.-11:59 p.m. Sun.
My wife spends Thanksgiving on the phone with family and those calls are definitely shown as peak usage. Thank goodness many are on VZW and mobile to mobile is free!--