Welcome back all looks like the fun begins, week four is here and gone with the flowers staring to stack. It looks like my suspicion was correct and the plants needed a PK boost from flowering.
I gave them a booster on the 10th and in the timelapse you can see how they responded. The K deficiency looks like it was halted from going any further and might have reversed it a little in the leaves.
I had to add a little food after all in the mid to late flowering stage, but you have to listen to what the plants are telling you even if you think they have everything they need. live and learn.