30 hour day in flower 18/12?

Since the 12 hours of dark is what triggers flowering, has anyone set their timers to longer "days" then 24 hours? Say a 30 hour day (18 on 12 off) or something along those lines?

I kind of answered that here..https://www.rollitup.org/t/possible-to-take-time-off-flowering-using-more-dark-hours-6-hours-light-18-hours-dark.170488/

IDK if a 18hr light cycle would destroy all the flowering hormones that built up, which could actually slow the flowering process..