I emailed the service manager at Chester yesterday and asked about the DME update and it's purpose. He replied....
"Hi David. In the event of a gear change that is inadvertently not completed, this software update prevents the transmission from becoming stuck between two gears. This new software version makes gear changes more reliable and smoother. Hope this clears it up for you. Thanks Gary"
I had this done at 18k service a month ago and have subsequently done a tour of the Alps and Pyrenees. No dramas or problems and Hilltop remap is as good as it's always been.