Sweet Seeds have a number of strains called "fast versions" which all finish early/middle of September.
Have grown almost all of their strains and can recommend them all highly - easy to grow, potent plants with great yields and results.
You can almost just plant them and apart from water, they will almost grow themselves, ideal for your purposes.
From what I have found out, it seems Dinafem/La Mota/Humboldt Seed Orginization may never open again. (these 3 breeders being the same company)
And yes, Humboldt Seed Organization has nothing to do with California, it is an umbrella company of La Mota and is based in Spain, the same goes for Dinafem.
Forget autos, grown outdoors and with only sunlight and not much day length, you would be lucky to get more than 10-15 grams from each plant.
Started early and planted out soon, you could easily get 50-100 grams per plant, if not more, from the "fast version" plants put out by Sweet Seeds.
Also, even though it is not an "fast version", Sweet Zenzation is another early finisher and will impress you with beautiful, sticky and solid flowers.
Hope this helps,.............
Organoman.