Generally The time stated by the breeder is off by a week or 2. For the particular strain you have the Flowering Time Indoor: 75 - 85 days (seed to harvest) Keep in mind it can sometimes be longer . Keep an eye on the Trichome colour to really tell when you want to harvest them. Cloudy (Head stone) or Amber (Body stone), all in the smokers preference.
Do some research on when to harvest. It doesn't have to be your strain, all cannabis is generally the same when it comes to signs of when to harvest.
Hope this helped