Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and over 20 years of experience in the legal field. I’m happy to be of assistance.
Regrettably, this is very difficult to do. It's not that the process for getting it done is hard (though it is slow). Rather, the problem is the very high standard applied to allowing an upgrade. The discharge status is intended to be permanent. While many in the military, myself included, were told that these things are upgraded or can be upgraded after (so don't worry about the discharge status), that's far from true.
To upgrade a discharge, you have to file a DD Form 293 (if within 15 years of the discharge) or a DD Form 149. Those boards have the power to review and upgrade a discharge. That being said, they only do so when you can show that the discharge was an error or an injustice at the time it was given. Positive life changes and the things you've done since the separation are not relevant to their review, because it isn't a merit based concept for them to upgrade. They only upgrade when, in their estimation, the discharge status shouldn't have been given in the first place due to ignoring evidence, clerical error, etc. Their goal is to correct the record based on error, not to improve your discharge status based on your having earned it...which is unfortunate, because I think many people do earn it and if this sort of review was done, we'd see more discharges upgraded....but that isn't how they review it based on the law.
If you have any further questions, please let me know. I invite follow up questions, so use REPLY for those. If you have no further questions then good luck going forward and please do not forget to rate my service with a top-three rating so that I receive credit for working with you today. Also, feel free to request me in the future, if you have questions concerning a different matter.