I had the update done and I had a serious lag 2 days later. My first thought was o no whats going to happen in winter. Much to my surprise the lag only seems to appear during warm up. I did drop 2 to 3 mpg average after the update, I added some FPPF to my last fill up as cold is in the forecast and gained 4 to 5 mpg average since. Average mpg has been 22 in this area until the update then it dropped to 19 until I added the FPPF now I am getting 24.