Then they packaged some autoflowers by mistake. Or, your timer is malfunctioning or malfunctioned recently, in which casue if it is now on an 18/6 schedule it will re-vege. More likely the breeder sent you autoflowers by mistake. Maybe some retarded ramification of making "fast" flowering plants that don't flower any faster tan average and have X% of ruderalis genes in them. This would be extremely bad luck if so, lol, or a breeder that has no understanding of genetics.
The nutes have nothing to do with it nor watering habits.
BTW, you are watering the wrong way. You should be getting the entire pot wet each time - no dry pockets. A minimal runoff in soil is fine and won't leach off too many amendments. If soilless, you should for for 10% runoff, religiously. Wait for top layer to dry and repeat. you don't pick the cc of water to give. that is dictated by what constitutes your substrate. you give what is necessary to get the job done propperly.
A photoperiod is 'dark-dependent'. It requires 10+ hours (varies) of unintrrupted darkness to cause flower phase. In the dark it produces a molecule that is part of a feedback loop. When the concentration of that molecules builds up (only produced in the dark) it sets off a reaction in the plant to shift to flower phase. It is impossible for a photoperiod to do so without a long dark cycle.