While the appropriateness of this has been debated in this forum, in practice a soldier who is in entry level who has been diagnosed with an EPTS condition will be discharged without benefits unless there is a clear indication of service aggravation. A PEB would not be convened.
In the past, the rule was that members with a Non-waivered EPTS condition may have been denied a PEB in the following situation:
"E3.P2.5. Members with a Nonwaivered Pre-Existing Condition
Service members who are identified with nonwaivered medical conditions or physical defects that existed prior to service may be administratively separated without referral into the DES when the medical condition meets all the criteria listed in subsections E3.P2.5.1. through E3.P2.5.4., below:
E3.P2.5.1. The medical impairment is identified prior to or within 180 days of the member's initial entry on active duty or active duty for training or full-time National Guard duty.
E3.P2.5.2. The medical impairment does not meet accession standards under DoD Directive 6130.3 (reference (f)).
E3.P2.5.3. The impairment is not a condition that is cause for referral to the PEB under enclosure 4 or Service supplemental medical standards.
E3.P2.5.4. Service aggravation of the impairment has not occurred. If the Service member contests the 'not Service aggravated' determination by the physician recommending separation, the member may request the MEB be forwarded to the PEB for review."
DoDI 1332.38.
However, the service aggravation is still presumed and the members does not need to show "clear" service aggravation. The military would need to show- at least under the regulation cited- that the aggravation has not occurred by a preponderance:
"E3.P4.5.2.3. Presumption of Aggravation. The presumption that a disease is incurred or aggravated in the line of duty may only be overcome by competent medical evidence establishing by a preponderance of evidence that the disease was clearly neither incurred nor aggravated while serving on active duty or authorized training."
However, this was changed with the 2008 NDAA:
"E3.P4.5.2. Presumption for Members on Active Duty for More than 30 days. The
presumptions listed in E3.P4.5.2.1., through E3.P4.5.2.3., below apply to members on orders to
active duty of more than 30 days, for purposes of determining whether an impairment was
incurred or aggravated while a member was entitled to basic pay.
E3.P4.5.2.2. After Entry
E3.P4.5.2.2.1. Presumption of Sound Condition for members ordered on active
duty for more than thirty days. This presumption applies in all cases in which a member,
on active duty for more than 30 days is found to have a disability and the disability was not
noted at the time of the member’s entrance on active duty. This presumption is overcome
if clear and unmistakable evidence demonstrates that the disability existed before the
Service member’s entrance on active duty and was not aggravated by military service.
Absent such clear and unmistakable evidence, the PEB will conclude that the disability was
incurred or aggravated during military service."
DoD Policy Memorandum on Implementing Disability-Related Provisions of the National Defense Authorization Act of2008 (Pub L. 110-181) (October 8, 2008.
So, the later rule is that there must be clear and unmistakable evidence to overcome the presumptions.
Now, under the latest DES regulation, DoDI 1332.18, Para. 7, here is the similar rule (restated):
"b. Presumption of Sound Condition for Members on Continuous Orders to Active Duty Specifying a Period of More Than 30 Days
(1) The Secretaries of the Military Departments will presume Service members, including RC members and recalled retirees, on continuous orders to active duty specifying a period of more than 30 days entered their current period of military service in sound condition when the disability was not noted at the time of the Service member’s entrance to the current period of active duty.
(2) The Secretaries of the Military Departments may overcome this presumption if clear and unmistakable evidence demonstrates that the disability existed before the Service member’s entrance on their current period of active duty and was not aggravated by their current period of military service. Absent such clear and unmistakable evidence, the Secretary of the Military Department concerned will conclude that the disability was incurred or aggravated during their current period of military service."
DoDI 1332.18, APPENDIX 3 TO ENCLOSURE 3
So, under current rules, unless a condition was noted on entry, a member on orders of 30 days or more (including IET trainees) will have the presumptions of service incurrence and aggravation that can only be overcome by clear and unmistakable evidence.