again, very, very, very appoximately
Latest collection time from shipper : 18:00
trucked to sub-hub sorting centre & arrive : 19:00
truck from sub-hub to air hub & arrive : 22:00
loaded & flown out : 23:00 (air sector)
arrive at super-hub : 01:00
sorting etc & depart again for air hub : 02:30 (air sector)
arrive air hub : 04:30
sorting etc & sent on to sub-hub 05:30
arrive sub-hub : 08:30
sorted sent on to receiver : 09:30
so in the whole process there are only 2 x 2 hour air sectors (average)
monday night through friday night
& there isn't any daytime air activity