Here in the Central PA region, ARTICLE 58 - HOLIDAYS & SUNDAY WORK, the supplement notes...
Section 1
Holidays under this Agreement shall be New Years Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, Day After Thanksgiving, Christmas Day, December 31st.
Section 2
All time worked in job classifications subject to hourly rates and worked on Sundays or holidays shall be paid at double (2) time in addition to the holiday pay, except in the case of any employee whose regular work period starts on a Sunday or holiday evening or ends on a Sunday or holiday morning...
Section 3
When operating schedules require that part time employees work on a holiday, they shall be given the next day off as the holiday. If required to work that next day, they shall be given the premium pay for holiday work. If not required to work that next day, they shall be given holiday pay. However, the work done on the holiday itself shall be paid for at regular rates.
In other words, the full-timers are making out like bandits. However, the part-timers are getting (CENSORED) - straight pay for working a holiday.