OOS Full Pay - Application deadline & Essay

<p>Hi, I am a parent, son applying to UT for CS Major. Wanted to know if applying by Nov 15th is recommended rather than Dec 1? He has to still write the Essay A and B. His Common App essay about a passion can be tweaked to go in as one of them? How important are essays in general for UT AO? Not much time left now.......</p>