http://www.digitalgametechnology.com/index.php/support1/manuals/clocks/dgt2010-na
The manual is there. From what I can tell, it doesn't automatically add the time at move 40, nor can it be set to do that. So, the player would be responsible to claim if 40 moves were not made in the first time control since the clock will automatically add the secondary time control, when time runs out in the first.
Looks like mode 19 will do that.
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