The china ban occurred around the same time Jamie Dimon of JP Morgan, Robert Shiller who won a nobel prize in economics and many other financial/economic analysts & experts claimed bitcoin was a bubble about to burst. That is likely what caused the last big drop in btc price.

People may have realized china isn't as big an influence on btc price as it had been in previous years. When the price didn't fall completely through the floor as it did in 2014, the last time china banned btc exchanges, they decided to call it a bottom and buy in, expecting the price to increase.

Bitcoin's price has always peaked late in the year. The reason for the price increase could be seasonal as well.

There could be other motives for it like Catalonia's independence. But that seems to be controversial and so we can ignore that for now.