how long can a plant stay without media?

[piaffe97]

I desperately need to repot my Den and several Phals. I've been using moss and decided to switch to s/h, but until it's shipped to me, my orchids are crying for help. I'm really temped to remove the moss (which is damp and awful looking) and leave the roots exposed until I get my s/h. Any advice as to whether or not that's safe? Thanks