Friend may have ruined 3 plants....

OK,
heres the situation:
Went away for a few days and asked my friend (who knows whats going on) to water and feed, once each, while I was away.

Watering - went fine I'm assuming

Feeding - Told him 3 plants to the right in the box were on week 8 and to just follow the FF feeding regimine....I should have been more precise in words chosen and said week 8 of flowering. He fed them as if they were in week 4 of flowering, not week 8:( Now they got a nice dose of Grow Big and Beastie Bloomz.
Question is, how much of a problem is this going to have in this 3 plant round?

Any questions or comments or ADVICE would be great, thanks!

btw, in soil....

It shouldn't kill them, but if the plants are in week 8, make sure to get a good flush or two in before you chop. If you're expecting to harvest soon (in the next week or two), then you shouldn't be fertilizing any more, rather using plain water. This helps to wash away the chemical aftertaste of the fertilizers.

In the future, this is what I'd do- if you have to go out of town, make up a big jug of the most MINIMAL mix you'd use. Not the base fert though- chemicals can interact badly in solution. You can always resume fertilizing when you get home, and it's not going to make a big difference in yield to miss ~2 feedings. On the times I've had to leave the plants with a sitter, I've left jugs of nothing but tap water, calmag, and a little molasses. The calmag and molasses don't interact significantly. That way no well-intentioned friend can screw up my crop!