Reporting on the 39.5 file downloaded from here and tried on a 15 with a 18 UAQ running 22.6: failed 3 times before I gave up. Each time around 30% completion I would get the error 20 code and then after a few it would revert back to the 22.6 previous version. Seems I am one of the lucky ones that radio actually does what it displays it will do with the error, but just wanted to report my experience. I may try a version between my 22.6 and goal to 39.5 files just to see if there is a minimum version to be on in order to go upto 39.5.