Somehow I get the feeling that the branch was told to reduce the number of special pioneers to a certain number and then the ones who didn't have enough friends at the branch were the first to be chopped. I don't know but I can't see them terminating all of them at once but if they did...wow.
I can see witness parents realizing that being a Bethelite or in some other form of special full-time service is not as desirable as they once thought. Who would want to go to the Schools they offer knowing that after they reassign you they can demote you at a blink of an eye.
I don't see it as being a leak as it is not confidential and they can share it with whomever they want. If a congregation had more than one special pioneer then the elders would get copies of the letters. What we saw was not the official template but a construction based on the contents of the letters. (The fonts were different). Anyhow, I wonder if any of them care about the annual meeting now?