It will take time for your clone to revert back to vegging, and it will prolly have some weird leaves. that depends on how long it was in flower. since you say it only sexed with preflowers then you should only get a time delay in its revert.
The plant it was cloned from...? that's the key... how long has it been growing, was it from seed or clone.
A good 6-8 weeks gives it some maturity, the more mature the better end results.
I have taken clones and put them directly into flower to sex them. the best way for that is to have a high humidity around the leaves. I had a fogger and bubbler with a dome over. and left one of the plugs out. It got real humid and I even had new growth and sexing. without roots. then I just put the plug in, take dome off and BAM! roots in a few days.
If you haven't grown this strain out before then you have no yield to compare with, and I'm sure your friends grow set up and style is different from you.
The yield you will get is dependent on your set up.
Get your plant reversed properly, so that you have normal growth. Take clones, have one of those clones be a mother. flower out your original reverted girl. Either way your yield will be good, so as long as your set up is good.