What Boz said, 7 days most of the times and not to forget I notify you all from the first minute.
Two reasons I do this: first, I might make mistakes of the deadlines, and it takes loads of time to check the time of each match, secondly it will be unfair to the rest if I set the deadline at match time, and the ones who will predict just before the match might predict better with the latest updates of the squads, injuries available players and formation etc..
I wish if these threads could close automatically, with setting time..