Utah's usual arrangement alternates holidays by odd and even year, with one parent taking the odd years. Whichever rotation you choose, name the exact hand-off times — a plan that says "Christmas Eve" without saying 6:00 PM is the most common source of conflict.
Utah's statutory minimum schedule (Utah Code § 81-9-302) gives the parent the children do not primarily live with one weekday evening each week — typically Wednesday — plus alternating weekends from Friday evening through Sunday evening, along with holiday and extended summer parent-time. Under the minimum schedule the midweek visit is an evening only and does not include an overnight. It is a floor, not a requirement: parents are free to agree to more time, and many do.
Expanded parent-time (Utah Code § 81-9-303) turns the midweek evening into a midweek overnight and runs alternating weekends from Friday evening through Monday morning instead of Sunday evening. The practical effect is the overnight count: expanded schedules push the number of overnights high enough to qualify as joint physical custody, which changes which child support worksheet applies.
Overnights are only half of it. Utah Code § 81-9-101 defines joint physical custody as the child staying with each parent overnight for more than 30% of the year AND both parents contributing to the child's expenses on top of child support — both parts, not just the calendar. divvi treats 111 overnights as the working threshold. Below it the sole custody worksheet applies; at or above it the joint physical custody worksheet does, which usually lowers the higher earner's payment.
No. The statutory holiday schedule is what applies when parents do not agree on something else. If you both agree on a different division of holidays, the court will normally accept it as long as it is specific enough to enforce — which means naming the holiday, the years each parent gets it, and the exact start and end times.