‘Night’ is that period between the end of the evening civil twilight and the beginning of the morning civil twilight. For all intents and purposes, first light should be construed as the beginning of civil twilight and last light as the end of civil twilight. The terms ‘sunrise’ and ‘sunset’ have no relevance when calculating daylight operating times for the VFR pilot.
So instead of using a simple event that is clearly defined you have to go through a series of calculations to get an extra couple of minutes at each end of the day using terms that are not officially defined?
Way to go...