MistaOCanswered grow question 4d ago Royal Queen Seeds states that their Hulkberry autoflower strain are ready for harvest in about 65 to 70 days. In my experience, however, such timelines – no matter which breeder – are quite unreliable when it comes to autoflowers. It’s not unusual for some plants to take 12 to 14 weeks to fully mature.
In your pictures, the trichome heads are unfortunately hard to see clearly, so I can only make a rough guess about the ripeness. Personally, I don’t do a traditional flush. Instead, I simply stop giving nutrients in the last two weeks before harvest and continue watering as normal – no extra water.
That said, if you prefer to flush, now would be a good time to start. In my opinion, it’s better to reduce or stop nutrients during the final weeks anyway, since the plant focuses more on ripening existing buds rather than producing new growth at that stage.