For Airport hours see the CAA Publication:
http://www.ead.eurocontrol.int/eadba...2018-12-06.pdf
Night time closure - details are contained in the Airport’s noise action plan:
There are very strict limits on the number of scheduled night flights that Southampton Airport may operate during the night period. The night period is defined from 23:00 to 06:00, or to 07:30 on Sunday mornings. The airport is permitted to operate 10 scheduled night flights per month, but not more than 100 in any 12 month period. However, occasionally flights operate during these times for unexpected reasons such as poor weather or as a result of en-route air traffic control delays. Additionally some ambulance flights carrying patients or transporting donor organs are accepted during night hours, for emergency medical reasons.
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