Catboat, What kind of DT are you using? There are several ways to DT a P-30 and the set up is different for each. If it is a pop up Stab then it is pretty simple to do. Here is a picture of a simple way to do it. This is on a glider but I have used it on a P-30.
The line from the left is attached to a spring and supplies the pull that moves the timer. The line on the right is attached to the stab and hooks on the lever which is held by the timer line. When the timer releases the timer line, the lever is released which releases the dt line.
This set up allows you to put more tension on the DT line so that the stab will stay down. If you hook the dt line directly to the timer the pull of the dt line can make the timer move to fast which can be important when you are making those long flyoff maxes. Hope that makes sense!