You read the Promotion Orders:

The Secretary of the Army has reposed special trust and confidence in the patriotism, valor, fidelity and professional excellence of LAST NAME, FIRST NAME, MI. In view of these qualities and his/her demonstrated leadership potential and dedicated service to the United States Army, he/she is, therefore, promoted from CURRENT RANK to PROMOTED RANK. MOS XXXX is awarded as his/her primary MOS on the effective date of promotion. Promotion is effective 01 MONTH YEAR with a date of rank of 01 MONTH YEAR.