Daylight robbery

As you all know, I don’t do policy, but every now and then I am tempted to urge legislators to use their intelligence. Yesterday was a case in point, when out of the blue friends spontaneously invited us to Sunday lunch, and we had to calculate what the time was. All our time pieces were scrupulously correct but some of them wrong, because officials had determined that official time had officially changed. This ritual is described as “putting the clocks forwards” or “back” as the case may be. Time itself is unperturbed, entropy continues, the sun is still shining whilst very slowly dying, but millions of citizens must adjust the time depicted on watches, kitchen clocks, microwaves, ovens, bedside alarms, video recorders, boilers, timed power plugs, cars and, as Borges might have said, Devices Which Keep Time that Have Been Forgotten.  

http://drjamesthompson.blogspot.co.uk/2013/10/clocks-back-time-forwards-traditional.html

The rational use of daylight was championed in the Special Report on Daylight Saving in 1908: To move the usual hours of work and leisure nearer to sunrise; To promote the greater use of daylight for recreative purposes of all kinds; To reduce the industrial, commercial and domestic expenditure on artificial light.

All that needs to be done is to find a time which maximises the use of daylight, and then stick to it, letting groups with special needs (schools, milkmen, burglars) set their own winter timetables.  For illustrative purposes, consider the origin of Time. Not the Big Bang, but the Observatory at Greenwich, for which the longitude is zero, and the Latitude 51° 28' 38'' N. At this place the shortest day (around 21 December) is 7 hours 45 minutes long and the longest day (around 21 June) is 16 hours 39 minutes.

Assuming that policy makers haven’t the time to read this blog because of pressing other engagements, here is a picture for them to glance at,  called Darkness at Noon, since it is suddenly unseasonably dark here in London. Given this startling turn of affairs, I am suddenly pressed for time as well. Can someone with better skills please

a) draw it better

b) solve the puzzle by choosing 6, 7 or 8 as the standard fixed starting time for Londoners, and draw it in?