military jobs question?

The Air Force would rather not have "job-locked" individuals join; it's all about flexibility and luck. There are a ton of papers you have to sign that state you completely understand that your recruiter is not promising you a particular job. Jobs are given out based on what the Air Force's needs. Job drops are at the beginning of every month. While your son is in the Delayed Entry Program, if his recruiter calls him, then that means one of his top ten jobs he listed is available. If the recruiter doesn't call, you'll have to wait until next month. You'll have two options when you receive a call from your recruiter: He can either take the job, or go into boot with either Open General, Open Mechanical, Open Administrative, or Open Electrical. If he does this, he won't know his job until the middle/end of basic training and will leave immediately after graduation for technical school.

EDIT:

The only way your son will have a guarenteed job going into BMT is if he were to join the Special Ops/Forces part of the Air Force (Pararescue, Combat Control, Special Operations Weather Team Specialist, Tactical Air Control Party Specialist).

No, the only branch that will assure training in a specific job is the Army

Persistence, do not take no for an answer.