The TG LAX office is open M-F 8:30 - 5 pm, Pacific time.

I would advise against phoning late Friday afternoon though. I called yesterday at 4:40 pm and received the message that I was 4th in line with a wait time of 8 minutes. I waited until 5 pm, and was then automatically removed from the wait list, likely because everyone had decided to go home for the weekend.