In 1665 Nikifor Chernigovsky murdered the voyvoda of Ilimsk and fled to the Amur and reoccupied the fort at Albazin, which became the center of a petty kingdom which he named Jaxa. In 1670 it was unsuccessfully attacked. In 1672 Albazin received the Czar's pardon and was officially recognized. From 1673 to 1683 the Qing dynasty were tied up suppressing a rebellion in the south, the Revolt of the Three Feudatories. In 1682 or 1684 a voyvoda was appointed by Moscow.. How many years after Chernigovsky fled to the Amur was Jaxa unsuccessfully attacked?