As a BIAB brewer (10+ batches), I'm mashing full volumes in my 10 gallon kettle. I heat my water/wort on a propane burner (Edelmetall) I've noticed that my mash temp actually increases during the 60 min mash from time to time. Today I heated 8.5 gallons of strike water to 157F (per Beersmith). I shut the heat off and then used a digital liquid thermometer and stirred the water vigorously up and down and all around for 30 second to ensure no hot/cold pockets. I hit 157F, mashed in thoroughly, (about 12lbs of grain) and then again stirred vigorously for 30+ seconds. Mash temp came in at 152F. Boom! Wrapped the kettle in two blankets. 30 min later I checked my mash temp after stirring again thoroughly and I was at 153.7F. At 60 Min I was still at 153F. I am wondering if I am getting residual heat from my burner that is continuing to heat the mash after the burner is turned off. I've not read anything about this in all my research and learning about BIAB. Anyone dealt with this, have insight into the cause, or have solution on how to navigate in Beersmith for future batches?