If you have read this post, you will know that the Shanghai premiums to London gold prices are a proxy for higher demand for gold in China. Because when the premium shoots up, the demand in Shanghai shoots up too. Compare the two charts yourself. (Second chart below is courtesy of Koos Jansen, In Gold We Trust, original link)
Now, we can also do the same for silver. Look at the silver premium chart between Shanghai and London below. I do not even need to know how much the Chinese demand is for silver, because the silver premiums speak for themselves. We call this "the power of deduction".
And these peaks in silver premiums magically coincide with a drainage in the SLV trust. Let's see what happens next, will SLV be drained too in the same manner as GLD?