I know I have trouble walking a straight line down my driveway after I have been stored upside down, but that may just have something to do with what I was drinking.

However I don't think it should affect your Phantom.

Phantoms should only be stored upside down in Australia and New Zealand

Old Geezer Posted at 2016-5-18 03:20
Phantoms should only be stored upside down in Australia and New Zealand

Actually I think you've cracked it, if the Aussies are upside down then so are we, so it must be ok as we are all doing it!

Dont thnk it should make a difference as its not powered on

I split the difference.  I store mine sideways...  (Which is the position its in when kept in the supplied Styrofoam case with the latch pointing up).  

Have you got the D1 backpack ? If so then just stand it up if your worried, then it's on it's side.

No way your camera is in fpv mode, right? Well, even if it was it should not drift....
And yes, all the other answers you got - quite enjoyable ;)