OK, her goes...........
The last of the X350 XJ, S-Type, X-Type models used the MMM1 NAV system. It was one DVD for the whole of North America. The 'Jaguar part number' shown on them was 1X43-10E898-xx. The suffix, i.e. -BD -BF etc. changed with the successive revisions. Without one in front of me I can't tell you exactly what year a certain suffix denoted. I do know the final revision for those cars was for 2011-2012, and carried the part number 1X43-10E898-BK. Unless some map company decides there is enough money in further updates for those systems, I don't expect you will ever find any.
As far as the other part number, the 6W83-10E898-xx tells you it is for the later MMM2 systems that used two DVD's for North America. With those, each DVD had roughly two-thirds of NA covered. One was the western 2/3 and the other covered the eastern 2/3. They were used on the 2007 on XK and the XF thru 2012. After that, all systems have an on-board hard drive for map data storage.
As usual, these things are a bit more complicated than some people think.
If all else fails, at least for now, the last version is still available from what used to be called Navteq, but now goes by the name HERE Maps. Go to the link below and select your car and model year and you will find the latest available for that car.
Cheers,