With the last timetable change there was minor changes to the weekend diagrams.
Saturday there is two diagrams that start from the late morning into the late evening if I remember right. There is a 3rd diagram which is attached to one of the others in the afternoon to make one 4 car and one 8 car train. There is no 377/5 on a saturday south of London.
Sunday is the reverse with an 8 car running up and down the BML. Nothing runs north of London tho **I think**.
This is all from memory and its been awhile since I last saw the diagrams myself. Note the weekend diagrams are the same as you will find on the Yahoo groups. (I know I put them up there).
Here is a link to the December 2009 diagrams, which will give you the correct diagrams monday-friday. Will dig up the new weekend ones when I'm back to work next week.
http://finance.groups.yahoo.com/group/Electrostars/files/Timetables/