i didn't mine any of AC but i bought all my coins and i have around 600k AC will i lose any of my coins if they were from the premined?
or the new code will only kill the premined coins in the dev's wallet?
No you won't lose them, and yes, it will only kill the premined coins in the dev's wallet.
What if the dev saw this thread and started distributing the premined coins to different wallet?