Auto pot 1 st run feeding question??

Hey guys !! My question is if 2 of the 4 plants bud earlier and need bloom nutes what do you do??? I'm running 4 autos with 12 gallon res. Or say one needs cal mag and rest dont? Any advice would be greatly appreciated!!!y

I'm sorry they will be 5 weeks on Tuesday. The 2 on the right are starting pre flower.

A+b nutrient there's no veg or bloom just a+b.

The chances of one plant needing calcium or magnesium is unlikely but you could hand feed or folier feed the individual.