Prompt Changing CSC for Galaxy S 2 Plus(GT-I9105P)

Hi guys,

I need an answer for the next question. If i change CSC version for my Galaxy S 2 Plus i will lose my warranty? I'm asking this because i have left more than 19 months of warranty and i wanna update my phone to official 4.2 because in my country there is no release and i guess it will take lot of time for Samsung to release it.

Also, if i have a problem with the phone and need to take advantage of the warranty, do i need to change to original CSC and original 4.1 android?