It is the policy. It's right there in the honor code
Former LDS students are not eligible to receive an ecclesiastical endorsement (See Withdrawn Ecclesiastical Endorsement below).
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Excommunication, disfellowshipment, or disaffiliation from The Church of Jesus Christ of Latter-day Saints automatically results in the withdrawal of the student's ecclesiastical endorsement and the loss of good Honor Code standing. Disaffiliation is defined for purposes of this policy as removal of an individual's name from the official records of the Church.