I-131 (re-entry) form fillout question.

[TBZ 0]

Hello, on the I-131 for re-entry, its asking for expected date of departure. What should I put if I'm already outside the USA and simply coming in for a week back to US to fill out/send out the re-entry permit ? I'm outside USA due to post-grad studies working on masters deg, so its not like I'm expecting on leave on X or Y day due to start of my program, but I'm already enrolled and was enrolled prior to obtaining my GCard via DVisa-online. I have the plastic GC not the stamped into the passport one. And I need this permit b/c it will be almost a year since they gave me the "move in" time of 1 year. Since that move in time I did get Soc sec #, bank acc, us-address. In other words, i need to prolong my move-in time to USA. And hence, I'm a little confused on what to put as my "expected date of departure". Sorry for any confusion w/this story. Thank you.