Can you diagnose this?? Drooping & lower leaf issue

Okay I have 3 plants, bagseed hybrids. I am growing outside and withiin the past 1-2 weeks the plants have started to droop a little. A few days later I noticed that some of the lower leaves started to spot and die.

I'm trying to figure out if this is a watering problem or a nutrient issue. I'm leaning towards nutrients but not sure. I haven't changed the original watering schedule but it has gotten colder and the soil is def staying moist for longer. So I'm going to stop watering as often. The nut schedule was every 3rd watering, once every 5-6 days. I had worked from half strength to full strength over the last 5weeks and didn't think to give more time between ferts, using 15-30-15.

Can anyone identify this???

Could it be overwatering and nute burn?

Oh and I also flushed them out 4 days ago and the soil is still moist....

over watering makes leaves lazy and sag. that is my diagnoses. 5-6 days sounds normal though.

I think the flush will help if I had a nute issue, unfortunately it has taken the soil a lot longer to dry out since then due to the cold temps. So this doesn't help if my other issue was overwatering. I'll find out in a few days hopefully.