I have done quite a few Allison A50 replacement TCM's over the years, but I've come across what is to me an oddball in the 2012 model year.
Typically they all seem to use OS 24266880 and Trans 24269908 but I have come across one that uses 24269909 which I do not happen to have. I've come across this same scenario with a lone 2011 truck as well, but I happened to have the file for that one. In this case I do not.