hey bud, if the sand bed is disturbed to much the anerobic layer, or portions of it may die off causing a cycle. Worst case scenario you release some nasty gasses into your water, but if your DSB is healthy, i don't think that should be an issue.
if you can move it safely, I reccomend putting a bowl at the bottom of the tank and pouring your water into the bowl instead of onto the sand, that should minimize disturbance.
You could also organized a workforce of MAAST'ers to help you break down and setup the tank as rapidly as possible.
"Maybe in order to understand mankind, we have to look at the word itself: "Mankind". Basically, it's made up of two separate words - "mank" and "ind". What do these words mean ? It's a mystery, and that's why so is mankind." ~ Jack Handey