Not to step on anyone's helpful insight, but:

Early in flower you can add a dose or two of your growth formula. Matter of fact, the Fox Farms Weekly Feeding Schedule (on their website) recommends this. I'd say iffy (situational) for mid to late flowering though, because of the plants inherant ability to scavenge the nitrogen from the leaves, which nitrogen makes the bud less tasty anyway, which is why we feel yellowing fans in flower...natural and desirable, and no big deal. Usually. The severe yellowing too early indicates an issue. Likely not a big one, but an issue nontheless.
But, the growth formula can elongate the buds. (stretch)

For mid-flower, It seems to me to be a bit early for such yellowing, and might end-up costing ya when it's time for the buds to fill-in. Nothing stored to build with. (leaves have already scavenged the nutrients and yellowed and died, which was where the plant was going to get it's stored nitrogen from) Too easy to goo too far too quickly with additional nitrogen in late flower. Bad things can happen quickly with this approach.

No, adjusting ph with nutrients isn't a good idea. Matter of fact, it's a real bad idea long-term. What if you need to water inbetween feedings on hot days, or if you need to skip a watering or two in the humid season? Best to get the right tool for the job, and respect your meds. :thumbsup: