Auto flowers are not

I have 3 plant going from bagseed 2 of the plants started flowering at 3.5 weeks at 18/6 cycle the other showed sex but no flowers the 2 afs are 17 inches tall I put them into hps 12/12 should they be on another cycle being they are afs ??

i heard autoflower strains, you do the 18/6 light cycle to get a higher yeild. it will still flower using the 12/12 cycle though

this was written in a review on the autoflower strain "SHORT RIDER" on the NIRVANA site

This is my first auto flower and it is an out standing plant. Nice hard buds and the most beautiful color of purple I have ever seen, which was a nice surprise.
the smoke is smooth and will have you ripped for most of the day. I had a small hit in the A.M. and out of it all day.
This is not a smoke for lite weights. And if you are a veteran of war then this is for you. No nightmares, just a long and rest full sleep.
I grew it in a 4"X4" tent and under a 1000w m/h lamp on a 18/6 schedule all the way though the grow.
Thanks Nirvana, I love doing business with your company.

I'm confused on auto also, I purchassed some Low Ryder Diesels autos from attitude, and there supposed to start flowering the 2nd to 3rd week ouot of the soil,
I have some that are at 6 weeks and just started showing signs of flowering.

so i still use the hps ? or go back to the MH?