If the territory the company operates over has more than one district, then it will have more than one district manager. Hence, the person who was promoted it just one of the district managers, so that
XXX, a District Manager at Apple Computers, was promoted to...
If the company has only one district manager, then XXX IS the District Manager
XXX, District Manager at Apple Computers, was promoted to...
Note that these men work at a company.
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