Interestingly True Ukranians didn't like the notion of their brethren being beaten and killed by Poles.....when it was clear the Polish conquerers would not relent they moved the church.
Kyiv Metropolia was Orthodox, not the Uniates. It was established by Cossacks and subsequently consecrated by the Greek Patriarch in 1620.
Why would the church have to move from the Poles in 1686 if the territory was no longer under the Poles?
Union of Brest and its aftermath
In order to oppose such restrictions and to reverse cultural polonization of Orthodox bishops, the Ecumenical Patriarch encouraged the activity of the Orthodox urban communities, or bratstva. In 1589 Hedeon Balaban, the bishop of Lvov, asked the Pope to take him under his protection, because he was exasperated by the struggle with urban communities and the Ecumenical Patriarch. He was followed by the bishops of Lutsk, Chelm, and Turov in 1590. In the following years, the bishops of Volodymyr-Volynskyy and Przemysl and the Metropolitan of Kiev announced their secession from the Ecumenical Patriarchate. In 1595 some of the renegades arrived to Rome and asked the Pope to take them under his jurisdiction.
In the Union of Brest of 1596, a part of the Ukrainian Church was accepted under the jurisdiction of the Roman Pope, becoming a Ukrainian Greek Catholic Church (UGCC). While the new church gained many faithful among the Ukrainians in Galicia and Volhynia, the majority of Ukrainians in the rest fo the land remained within Eastern Orthodoxy with the church affairs ruled by then from Kiev under the metropolitan Petro Mohyla. The eastward spread of the Union of Brest led to violent clashes, e.g., assassination of the Uniate archbishop Kuncewicz by the Orthodox mob in Polotsk in 1623.
In 1686, 40 years after Mohyla's death, the Orthodox Church of Kiev and all Rus' was transferred from the jurisdiction of the Patriarch of Constantinople to the Patriarchate of Moscow, established a century prior to that. This led to the Ukrainian domination of the Russian Orthodox Church, which continued well into the 18th century, Feofan Prokopovich and Demetrius of Rostov being among the most notable representatives of this trend.