via the NHL,

Dec. 20-27: Holiday roster freeze in effect: For all players on an NHL active roster, injured reserve,
or with non-roster and injured non-roster status as of 11:59 p.m. (local time) Dec. 19, a
roster freeze shall apply through 12:01 a.m. (local time) Dec. 28, with respect to waivers,
trades and loans, subject to the exceptions provided for in CBA Article 16.5 (d)

Dec. 24-26: Holiday Break (no scheduled practices – dressing rooms closed)