I got my first Phantom 1 1.1.1 in April 2014. It came with ver 4.00. First time I connected it to assistant software, it said there was an upgrade to ver 4.02. I never did the upgrade for fear of screwing something up and it still flies fine to this day. I kept trying to reset home lock and course in the air and never had any luck. I figured that might be an option in version 4.02. I asked many people about doing it with my Phantom and could never get a definite answer so I gave up. Two weeks ago I got another P1 version 4.02. It was only $379 shipped so I thought a spare would be nice. I took it out to fly and was able to reset hl and cl in the air. Cool. So I guess it was because of version 4.02. I was out flying this morning and though I would practice resetting hl and cl. All went well. I had to go and gas up the car and was thinking about this and then it hit me. I wasn't flying my new Phantom but the older one on 4.00. Surprised the crap out of me. So it is possible. So after all these months, I have my answer.