UL frames sold as upgrades for the PMR took different triggers to the stock and aftermarket frames for all other DM and PM markers - I would have to assume that '09 PMR UL frame is the same as the PMR UL upgrade frame. That being the case, a trigger for the DM8 frame would not fit your frame, as neither would a DM9 trigger.
For comparison, here are the Critical triggers for the two frames: -
DM8 frame (and other DM/PM UL frames)
PMR UL frame