This document is not agreed and was written in Febraury. Things have moved on a bit since the Workshops.
Remember this document is when you have walk sequencing and delivery methods.
But you have to read the whole document as there are two major constraints , the first is the arrival of wave 2 of your mail once you have sequencing and the new delivery spec.
So if you dont recieve your 40% of mail until 10 in the morning and you then have to prep , do your redirections , dead and tie up , travel out plus replishment time , then you will probalby struggle for a 3 and half walk. If you have your second 40% at 0900 you may get 4 hours in and if your recieve it early maybe a long span. Of course if you choose longer attendances it may be longer spans but those two criteria still remain at what time do you recieve your 40% and the last letter of 3.
Remember the maximum span includes replishment ( dead time ) and travel time.