You can set the max time in the Kia Access app, and probably in the car's system settings. I think there's a 5 and 10 minute option, but maybe a 1min as well?
Some other rules:
- All doors, hood, and trunk have to be closed (and locked once you hit that button before the start button)
- If you open a door, you have something like 20 seconds for the car to detect the key inside the car or it'll shut down (not enough to have detected it when you unlock the door to open it, which is odd)
- If you hit the brake (ie to shift into gear) without the key being detected, it will also shut down immediately