Answer for I misjudged the size of some of our food and as a result have a substantial amount of both plotboost and plotstart left over. Should i apply excess to some of my plots or hold onto it for next year?

Great question! If your pH was really low you can apply a “top dress” application of PlotStart over the plot when it is already established. If it wasn’t too bad (>5.7), then I would just hold onto it. PlotStart has a shelf life of over 2 years.
PlotBoost can be applied up to 3 times per growing season, so in the fall about every 30 days until a hard freeze hits. If you want to save it, the product can save for up to 4 years!
Either way you are in good shape both this year and next year as all the effects of the products are residual, meaning it will stay in the soil and continue to build its ability to produce great plots year after year.