sir_isOanswered grow question 4 years ago Yeah I've had that happen with heavy indicas (which I consider mostly between sativa and ruderalis, so some "fast" things are practically autoflowers).
I had some similar results with some other indica dominants (flowering within 6-8 weeks), a thing I call Sparse, and HSO Black D.O.G.
Especially if you're used to more sativa-like plants, it's confusing. Seasonality, nutrients and such also affects that. Recently I've had plants grow fo r ~10-11 months (coz they were planted in winter).