Providing more information about your cook would be helpful. I recall you have a P10. If that is the Bradley you used for your cook, and the times you are recording; that is a very long time. If you are using one of the other Bradley's that time is not that far off. The other Bradley's struggle to get to that temperature and the cook times are about the times you are recording, but the P10 recovers very quickly and keeps steady temperature. I'm also assuming, at 4 pounds it was a boneless cut, so the butt should have cooked even faster. Each cook, and cut of meat is different from the previous cook. The 1.5 hours per pound, is a guideline for butts and brisket, at the temperature you used. It could take a little longer or a little less.
I have a couple of questions (if you are using the P10):
1) I feel there is a discrepancy of what temperature is being displayed, and the actual cabinet temperature. Are you sure the cabinet temperature was 225°F. If you have a third party temperature probe, do a test run with the Bradley - empty. Remove the vent and stick the probe through that opening. If the temperature readings are correct, then with the P10 use a cabinet temperature of 250°F to 275°F. Adjust your cook times, because it will cook much faster
2) What is the internal temperature of the meat you are bringing your pork butt to? You should be looking at a temperature of 190°F - 205°F (depending on the texture of the meat you want).
3) Was the meat partially frozen (not completely thawed), when you placed it in the Bradley??
For my own information, I would like to know what type of smoke flavor, and how long you applied smoke.