This "title" without any text in the body of your post doesn't mean a whole lot. "$10 more for unlimited"?? $10 more than WHAT.
Plans are $30 more?? There are MANY differing plans with differing prices. ALL plans wouldn't necessarily be $30 more. Some may be LESS than $30 more and some may be MORE than $30 more.
If you want some help understanding something, you need to provide more information about what you want to know.
I switched to an unlimited talk/text and data plan this summer and it was $10 more for one line. If you a line, it is $20 more per line.