If they sell their BLOCK they purchased at Bittrex back into the wall at Bittrex they are perfectly welcome to take their BTC and go buy block somewhere else if thats what they choose to do.  It is their BTC they can invest how they wish.  There are no arbitrage opportunities as BLOCK cannot be withdrawn or deposited from Bittrex.

We maintain an account for the ICO that has the coins that were being sold and the BTC from those sales for our BUY/SELL walls only.  It is all tracked through there, volume created by people buying above ICO price does not count towards the ICOs total sales.

The statements above only stand for the 48 hour buy back period.

Thank you,

Ryan @ Bittrex