Bt technologies have significantly reduced the amount of issues we have with caterpillar pests but it is not immune.
See the detailed information from Phillip Roberts about stacked gene cotton and scouting for worms.
https://www.ugacotton.com/2018/07/scout-all-cotton-for-corn-earworm-2/
Stink Bug Thresholds
Adjusted up or down based on the number of susceptible bolls present: Check bolls that are between quarter and 50 cent piece size.
3rd, 4th and 5th week of bloom – 10-15% damage
2nd and 6th week of bloom – 20% damage
7th (+) week of bloom – 30%
There is an app called the GA Cotton Insect Advisor that is free for your use. You plug in what stage your cotton is and what you are seeing in the field and it helps you decide when to spray and with what.