Mix together the vinegar, coleslaw mix, mayonnaise, 1/2 teaspoon salt, and a few pinches of pepper in a bowl. Cover with plastic wrap and refrigerate until ready to serve.
Drain and seed jackfruit. Pull apart with two forks or use a hand mixer on low to break apart.
Add the BBQ rub, 1/2 teaspoon salt, and 1/2 teaspoon pepper to the jackfruit and combine.
Heat the oil in a large skillet over medium-high heat until shimmering. Add the jackfruit, tossing occasionally, until fragrant, about 2-3 minutes.
Add the BBQ sauce to the skillet, reduce heat to low, and cover. Stir occasionally and cook about 5 minutes or until tender.
For the buns, heat up a little vegan butter in a skillet. Add buns, cut side down, and toast until golden and lightly browned in spots. Serve jackfruit on buns with coleslaw and pickles, if desired.