Thank you for your question. TVC's program criteria and online intake form are found on their webpage. Please feel free to complete and submit the online intake form at TVC's site.
 

In general, someone discharged with a less than honorable discharge (such as an other than honorable (OTH) or general under honorable conditions (GEN)) can apply to the appropriate review or corrections Board for their branch of service. The person seeking an upgraded discharge has the burden of proof, meaning they have to submit an application form as required and enough evidence to prove to the Board that the upgrade should be granted. Evidence can (and should) include information that is not part of the official personnel file and service medical records. Still, it is important you review your official records as a first step so you can determine the type of additional evidence that will be needed.
 

For a veteran with a mental health diagnosis, treatment records and a psychologist/psychiatrist/therapist's opinion letter can be strong evidence to support an application for an upgrade. It is similar to a "nexus opinion" for VA benefits purposes, BUT the evidence should also connect the reasons for discharge (behavior change, misconduct) and to the trauma and mental illness. 
 

Thanks again and we wish you luck!