I plan on getting the lightening kit soon. I figure it will be easier to sell the Dl1608 when I upgrade to the DL32R if it has a lightening plug.
Apple came out with the lightening plug right after the DL1608 hit the shelves. I'm guessing when Mackie made the switch to lightening connector, they probably had a stock pile of 30 pin boards that never got used.
I have no idea if this is true or not, just a guess.