TDIU, but also P&T? What?

Hi Everyone,

I am currently 90% Sc'd and was just granted TDIU. When I read the letter, this is what it says:

You have one or more service-connected disabilities:Yes

Your combined service-connected evaluation is: 90%

You are being paid at the 100 percent rate because you are unemployable due to your service-connected disabilities: Yes

You are considered to be totally and permanently disabled due solely to your service-connected disabilities: Yes

You are in receipt of special monthly compensation due to the type and severity of your service-connected disabilities:Yes

I am most interested in the section where it says I am Permanent and Total. But isn't TDIU just temporary? Can anyone shed any light? Also, I found out about the poverty level earnings. It IS BASED on you and your dependents. 

Thank you,

SECFO