Presumably they have sent letters to foreign language congregations to explain how on earth this is supposed to work.
The letter states that when two congregations work in the same territory the service overseers must come to a mutually acceptable agreement on how to proceed.
Normally native language congregations don't work in the same territory. Only foreign language congregations work in the same territory as other congregations.
In other words, this letter tells foreign language congregations to see for themselves how they're gonna proceed without foreign language territory maps....