justification is telling a reason why and on what you are going to use the ip's on, If you say 'posting' people might think you are using it for spam, which probably is the case. I'm sure that no one will give you extra ip's to let you abuse it.

Notice: Not telling you are using it for that goal, But that is the only thing i can make of it when reading this post. Apologies if it offended you in any way