For everyone who uses the MSU - Michigan State University article for guidance -
"How to choose and when to apply grub control products for your lawn."
https://www.canr.msu.edu/news/how_to_choose_and_when_to_apply_grub_control_products_for_your_lawn
I emailed the author of the article (a doctor and professor of entomology at MSU) and asked him about the recommended dates of applications. He said those recommended dates in the article are for the Michigan area, so everyone needs to adjust the dates according to their own particular area of the country. I specifically asked him about the Southeast US, such as Florida, Alabama, Georgia, Tennessee, and the Carolinas. He said it would range from about 4 weeks earlier [than the dates in the article] for south Georgia to about 3 weeks earlier for the Carolinas. Everyone should check with their own local Extension office for more specific timing for their area.
I also asked about Sevin and carbaryl, and he said he would be updating the article to show under the Available Curative Products that the Sevin Lawn Insect Granules no longer contains carbaryl.