after talking it over,at long lengths, with my buddy who also grows and iv decided to wait till my Sour Diesal is about 2 weeks out from chop before i pop my auto seeds in the pots and start my purple garden, so id say 3-4 weeks is a lil iffy, male autos typical sex at 2 weeks and females at 3, so give yourself a little buffer time so your not fumbling trying to chop in time, wait till 2 weeks then it will be safe to pop them seeds in.
as for your bumped question, its hard to tell really usualy buds put on a majority of their weight in the last 3 weeks or so, but id say it looks around 2oz, possibly more, that girl there has some nice lookin budding on the lower branches and thats quite a nice top, again hard to say seeing as your about 4 weeks out, she will start bulking up soon, but 2oz is a good prediction, i had a plant half that size on my first grow that i thought was gonna be like half a oz it looked pathetic compaired to my friends but for what i had it wasnt too bad really, she yielded just over 1 and 1/3oz so it can be difficult to guess, keep that nice lookin girl happy and youll get a great harvest.