The Wave Auction is starting from January 1st, 2020, 1PM UTC (Previously Dec 19th 2019) and is the public sale for the HollaEx token (XHT). You can deposit and start placing bids at any time to purchase the HollaEx Token (XHT).
You can already start doing so by signing up on HollaEx.com depositing funds to your account and preparing your orders before the Wave Auction starts.
The Wave Auction is the public sale of HollaEx Token (XHT) where bids are placed to buy the random waves that distribute the tokens as described in the whitepaper. The waves come randomly but on average occur daily and each wave will distribute a random amount of XHT to the top bidders.
Learn more about how the Wave Auction works here.