I want to remind you that in spite of the claims by The Episcopal Church, nothing in their current Constitution and Canons prohibits a diocese from leaving one province and moving to another.
This is correct as far as it goes. Nothing in the Constitution and Canons of TEC explicitly forbids a diocese removing from the church and transferring to another, just as nothing in the US Constitution expressly forbids a state leaving the Union to align with another country. That matter was dealt with by the Supreme Court (Texas v White, 1869). The court found that the underlying importance of the concept of the "union" of the states literally "goes without saying." The same is true of the union of the dioceses in The Episcopal Church.
The Constitution and Canons of TEC make ample provision for the division, creation, and merger of dioceses, and for the cession of territory from one diocese to another. (The original dioceses were contiguous with the states, and in fact were called "states" in the earliest versions of our Constitution.) But it goes without saying -- and isn't said -- that no diocese is free simply to detach itself from the "national church" without the permission of that church through the General Convention in "union" with which it becomes part of the Church in the first place.
The only provision in our Canons for diocesan autonomy from TEC applies to missionary dioceses outside the territorial boundaries of the United States, and then only with the approval of General Convention.
Tobias Haller BSG