Hi
@Centipede! If the auto plant is under 12/12 light schedule for its entire life, yes yield will be severely affected. However, if you apply 12/12 only for the last 2-3 weeks, this should not impact the yield so much. I'm currently doing it so I can have photos & autos, flowering in the same room (only for the last 2 weeks, once all the bud sites are developed and just need to fatten up). Hope this will help, keep us up-to-date and happy growing 👊