What would you do?

I'm flying UA 837 SFO to NRT on 12/9 in E+. I'm in seat D on the aisle on a 747 config. Every seat in E+ has been taken. Up until yesterday the entire aircraft was full in E+ and E-, but suddenly a whole section of E- seats (about 24 or so) emptied out in rows 37, 38 & 39. I'm guessing a group tour booking canceled out (or rescheduled). So there are entire empty rows right now behind me. I'm not a big guy, so the extra 6 inches while nice, aren't necessary. Should I;

1) Stay where I am? Keep the aisle in a full E+ row.

2) Move into one of the empty rows on the aisle in E- and hope that it doesn't fill up with a bunch of other people (which it may not since we're only 2 days from departure). Which will almost certainly guarantee that somebody else will take my E+ aisle seat.

3) Stay where I am in E+ but wait until check-in and see if there are still empty rows in E- and try to grab an aisle seat that has an empty adjacent seat at that point.

Your opinions are welcome?