Just curious because "APD-40" is the name of a major highway in my hometown of Cleveland, Tennessee. The only other usage of this term OOU appears to be the designation of a US Navy Destroyer. If one of these is the origin, the latter seems the more likely, yet the highway is overwhelmingly more prominent.
What even intrigues me more here is that there appears to be nothing else noteworthy in Star Wars that uses the abbreviation "APD" (eg. no such thing as "APD class" droids). Only usage of this term appears to be one time in the book ''Children of the Jedi: Star Wars Legends'', too.
Very mystifying to me, and I find it hard to believe that this somehow just happens to be a coincidence.