I want to know why Jake and the NeverLand pirates was cancelled in the first place? And seeing its open ending, is there any information of how the show would have ended or any plans for releasing some kind of resolution of its story?
According to the Jake and the Never Land Pirates' Disney Fandom Wikipedia Page, it was canceled "in light of Mickey and the Roadster Racers".
Disney executives announced the show was cancelled and would not receive a fifth season in light of Mickey and the Roadster Racers. The last episode aired on November 6, 2016.
Doing some more research I found that 'Jake's' writer Brian Swenlin is the one who moved onto Mickey and the Roadster Racers. I have not found sufficient evidence to conclude if 4 seasons of 'Jake' was always planned this way and/or any plans on what a potential season 5 would of been.