
I have only ever used the bleeding to pinpoint the start of the season, which I have usually been checking for for a week or so, based on other signs. A bitch will usually urinate more often just before a season, often stopping and weeing tiny amounts, like a male scent marking, though usually done squattting.
The genitals will have swollen slightly, and by the end of the first week ofthe season may be very obviously bigger than normal. I usually judge the season over after all sign of vulval swelling has gone,as long as at least 3 weeks has elapsed since she started. with my girls this may be nearly 4 weeks! Err on the side of caution!