Just to clear up any confusion, since this has been answered already a few times..
ETNX does not want your ETN or your ETN wallet, ETNX recommends everyone use a new ETN wallet to prepare your keys or mnemonic seed words before the blockchain snapshot occurs on block #280,000 so you can claim your ETNX after the fork. Don't even risk your main wallet, just create a new wallet and prepare your keys before the fork happens. Do anything you like with your ETN after the blockchain snapshot occurs. Transfer your ETN back to safe keeping, or exchange it for BTC. Just need to have ETN in your wallet before the blockchain snapshot which occurs right before the fork on block #280,000 and prepare your preferred method to restore your wallet and claim your ETNX. Otherwise your unclaimed tokens will be locked away forever on the ETNX network! Stay safe and we look forward to growing with you.

If you make a desktop ETN wallet, for the ETNX airdrop, and send your ETN there before the blockchain snapshot occurs. Then you are in control over your web wallet securely and you have prepared your ETNX wallet on the ETN chain before the snapshot, so your ETN & ETNX tokens are safe and the wallet keys and seed are just for you to regenerate your wallet and claim your ETNX. Right after the snapshot, you can send your ETN back to your web wallet and claim your ETNX with the seed or private keys you just made specifically for the airdrop.