I just left PBI, I can tell you it's 24/7 as far as flights depending on the carrier, smaller airlines counters are closed after 1:00. There are some food vendors that they tell me that by 12:00 they close and reopen around 7:00 depending on the vendor.
Don't know if the airport actually shuts down but I can assure you that everything is closed and there is NO activity after 9-10 p.m.
6am
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