Standing up ends the prone condition. You can Take Cover while prone to hunker down and gain cover against ranged attacks, even if you don't have an object to get behind, gaining a +4 circumstance bonus to AC against ranged attacks (but you remain flat-footed).. As the title asks, my group has been running it as though being prone both lowers the prone thing's AC -2 while benefitting an attacker with a +2 to hit. I don't think this is the correct way of doing it, as when prone, according to Nethys, the prone character has a -2 to AC and to ATK rolls. Nowhere does it mention a +2 to anything or one.
PRONE CONDITION You're lying on the ground. You are flat-footed and take a -2 circumstance penalty to attack rolls. The only move actions you can use while you're prone are Crawl and Stand. Standing up ends the prone condition. You can Take Cover while prone to hunker down and gain greater cover against ranged attacks, even if you don't have an object to get behind, gaining a +4.. 10 So, this is just a clarification about how a character's AC interacts with the Prone condition aside from the Flat-Footed condition. Mostly because being prone gives you the ability to Take Cover and some people I'm playing with understand that being prone gives you standard cover against ranged attacks even without taking cover.