Tropicana Cookies Autoflower

Leaves on the colas starting turning purple, a lot of pistils started turning brown this past week and the trichome production ramped up -- so I'll hopefully be harvesting them within the next few weeks. Minimal vertical growth on all 3 plants this week. No change in nutrients but I moved up the watering to about 0.75/1l per plant per 24 hours. Right plant is still suffering from what I think is sunburn because of its height/proximity to the lamp. Unfortunately my tent isn't that big so I will just have to deal with it. Any and all advice is appreciated. TIA, and happy growing!