In 1415 the division between GDL and Muscovite Metropolitanates was definitely established (however it had appeared several decades before). The division lasted until 1685. Both Metropolitanates were autonomous under Constantinople. The Muscovite one later became autocephalous.
No, the Grand Duke tried that, but Constantinople nixed it. A precursor of Isidore the Apostate's consecration, Met. Gregory Tsamblak was promoted by the apostate GD Vytautas (baptized Orthodox Alexander) and the equally apostate King of Poland Jagiello (baptized Orthodox Jacob) in 1415 as rival to the legitimate Metropolitan Photios of Kiev and All Rus' (already resident in Moscow), as part of the latest union scheme at Constance. Met. Photios denounced the action, and Constantinople excommunicated Gregory and abolished any claims to Metropolitan status to Lithuania in 1420, while Met. Photios re-established his jurisdiction in not only Lithuania but Galicia and Poland as well with visitations in 1420-1, 1423, 1427 and 1430. Gregory disappeared without a successor. Met. Isidore, before becoming officially the Apostate, was welcomed in the sees of the Commonwealth on his way to and from Moscow for his enthronement as their metropolitan. Met. St. Jonas' jurisdiction was recognized in the same sees in 1451 after the deposition of Isidore the apostate and the restoration of Orthodoxy, as I mentioned above, and after 1458 when the powers that were in the Commonwealth-i.e. the Vatican's dutiful sons-got most-but not all-of the bishops to recognize Latin ordained Met. Gregory the Bulgarian, Met. St. Jonas' successor Met. Theodosius in 1461 summoned the bishops of All Rus' to swear on the tomb of Met. St. Peter the Galician allegiance to him as their legitimate primate and condemn "Gregory, excommunicated from the Holy Catholic Church, who calls himself 'Metropolitan of Kiev.'" In due time, Gregory would try to get recognition in Moscow, as would his "successors." The situation wasn't regularized until 1589 in the context of the regularization of Moscow autocephaly and patriarchate.
The Greek Met. St. Photios had been consecrated as Metropolitan of Kiev and All Rus' and arrived in Kiev in the beginning of the Church year 1409 (a day less than a year after his consecration in Constantinople) and living there, conducting the affairs of the Church in the Commonwealth, before continuing on to Moscow half a year later for Pascha 1410 for his enthronement. His successor Gerasim was the protogee of the Lithuanian prince Švitrigaila (another apostate, baptized Lev) brother of the King of Poland, and consecrated by Met. Photios as bishop of Wolodymyr and Volhynia and Brest, then translated to Smolensk before going to Constantinople on Met. St. Photios' respose to be appointed as Metropolitan of Kiev and All Rus', before his patron suspected him of treason and had him burnt. His only know act was the consecration of the archbishop of Novgorod, not in the Commonwealth.
