Call them during working hours and inform them of your late arrival after hours. They will instruct you on what to do and how to get in.
There is a call box at the office building for late check in. There is always supposed to be a night ranger to answer it. They will know you are coming in late if you let them know when you made your reservations.
You'll have to find the emergency ranger contact phone. Check in is usually between 8 am and 9-10 pm.
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