The above answer is correct, only approved visitors will be allowed. Your friend has to submit your information to the campus leadership for approval, there is also a deadline weekly for visitors Info to be submitted.
Visits are on Sundays for clients and it also depends on their progress in the program itself. I believe visit times are 12pm-6pm on Sundays. They are required to fill out a visitor form for you to be able to get on the campus past security.
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