Just out of curiosity how are you getting such a high PQD with while averaging 600 miles per segment? You're pretty much at 50 cents per mile. If you're getting the premium + Y/B fare PQM bonus then you're really at an astonishing spend/PQM.
Seems like you're falling through the cracks of the system since you'll easily hit the 1K PQD requirement but barely hit the silver PQM. Usually its the other way around for most people.