This has not been my experience.
I have the tow package installed (not sure how that corresponds to the tow module you have mentioned) and the vehicle will roll back if on a hill and the auto stop is engaged. It can be alarming, especially when it coincides with hitting the accelerator and expecting the vehicle to move forward. The auto stop/start desperately needs to be re-tuned to start the engine much sooner, and to not engage if the vehicle is on a grade which would cause it to roll back. I do wish it was considered a safety issue and either allow for it to be permanently off, or resolved.
For what its worth, the auto stop/start on my Disco V is excellent. One of its only good qualities as compared to the Grenadier.