Flag spawning:
By current rules of WNL, flags spawn at 2:00. Same is the standard in NA at the time of writing this guide. (16.6.2014)
Flag spawn is random, you can't do anything to change where the flags spawn. There are 3 fixed flag spawns in a map. You should learn the flag spawn locations and keep them in mind when thinking about tactics.
Raising the flag up:
If team A has a player on the flag, and team B does not have any players on the flag, flag of team A will be raised.
If both team A and team B have a player on the flag, neither flag will raise or lower.
If team A flag is up but they have no players on the flag, team A flag will start to lower.
Mounted troops do not raise the flag or prevent the enemy from raising it.
Winning by flag
Method 1: You can win by raising the flag all the way up before the time runs out. Keep in mind, this is impossible as long as your opponent has anyone on the flag, as your flag will never go up as long as your opponent has even one player on the flag.
Method 2: When the time runs out
If team A has the flag higher, and nobody is on the flag, team A wins.
If flags are at the same height and nobody is on the flag, draw.
If team A has the flag higher and both teams have players on the flag, team A wins.
If team A has the flag higher or the flags are even, and only team B has players on the flag, team A flag will lower and team B flag will be raised.
If during this overtime team A gets a player on the flag, team A wins.
If team B leaves the flag, team A wins.
If team B flag is raised to the same level as team A flag, and team A gets a player on the flag, draw.
If team B flag is raised above team A flag, team B wins.