Lets see what happens.
Either bitcoin is very underpriced or GBTC users are happy to pay a heavy premium.
Dumping into the opening on a Chinese exchange shows the degree of desperation from bears - yes you will have to cover your positions

Both are true. GBTC is the only option for some classes of funds (so heavy premium), and bitcoin is underpriced. This is a decent arbitrage opportunity.
If someone is really serious about buying BTC, I bet they would be able to buy them on a regular exchange or from some mining company in bulk, even if they preferred an ETF. I know about the advantages and ease of use for people who are already active in that sector, but I don't know if this really warrants a markup of over 55%... This is quite steep!
There's a weird chicken-and-egg thing here. Could be wrong, buuuut:
a) Assessed market value without publicly tradable funds: $238.82.
b) Assessed market value
WITH publicly tradable funds: $420.00 ($42 sale price of GBTC x 10 shares = 1 BTC)
As soon as the orders placed COULD become filled, the market shifted from a) to b), revaluating it.
That is the most optimistic explanation.
We're in one of those rare instances where supply or demand is severely pinched. Most actors don't know how to respond...until a trend emerges.
Success is far from guaranteed here, but this day ACTUALLY coming can't hurt the bullish scenario in my view.
The key IMHO is on the red lined text. I consider the GBTC the first "crystal clear" way for someone to get BTCs and not worrying about losing their money. This would take others to imitate or get passed by by businesses/initiatives like this. I've yelled much too long about the "dark" non-ledgered bitcoin transactions on almost ALL of the exchanges.
This has to end. The price will definitely find its way - thats how free market works. For the 1st time, I'm happy an "exchange" is starting its business.