If anyone is interested, my timeline (London VO) is:
Application received Oct 5, 2012
Sponsor approval Oct 31, 2012
Decision made April 15, 2013
COPR received April 16, 2013 (the issue date says April 12, so ECAS has a slight delay).
During the whole process, my sponsor received the AOR and sponsor approval and thats it.
Regarding being in process after submitting additional documents, it varies between cases but I wouldn't expect it to take the 4 months they mention. There's a spreadsheet you can have view if you go to the London thread in this forum (i cant post links yet as i'm under 10 posts i guess), to get a rough idea. One member here found out that their file was abandoned for months until they emailed them so get in touch with London after maybe a month just to check things are okay.
London seem to be going at a faster pace lately so hopefully it won't be too long for you!
congrats im not far too approved in december just like mandy,waiting for my turn too cant wait to be with my hubby anymore
seems like an eternity ,everyday i feel like emailing london to know about the status but hubby asking me to wait for the duration it says on th e website i have no more patience this waiting time seems unlasting ,wish london will be fast to give decision so we may know what to do as if my life is on hold