They have started flowering. the 12/12 rule is a bit misleading as plants will flower within 13/11 schedules as well.
Your little ladies are becoming women. Make sure to give them lots of love. It looks as if they have been in flowering for a week or so now as well because in week 14, they were in flower too.
Your diary does not list a light but says its in doors, guessing you growing just off of the windows light.
Will be interesting to see the results at the end of your grow. If you have a light meter you should mesure the stregth of the light coming into the window a diffrent points in the day and trying ti find an average of how much they are getting.
Good Luck!
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