Understanding Turboactivate trial extensions

Hello,

I'm having trouble understanding how turboactivate handles trial extensions. I understand that as of 3.x trial extensions are built into the turboactivate wizard. I also understand the trial extension mode only shows when the trial days = 0.

Do I need to do anything special other than generate a extension for the user to input? Or will turboactivate extend the trial by itself when the user gives them a valid extension and then the trial will be extended upon my next call to check trial dates?