Can you PCS early a few weeks from Korea back to the states?

When it comes to DEROS date, you can leave 5 days before or 5 days after. Anything other than that you would have to do a 4187 with a good justification. Even if you have early report authorized, you cannot leave before your DEROS without a 4187.

Your orders will need to say Early Report Authorized. If they don’t it’s usually just a 4187 signed by your Battalion Commander sent to the branch manager

In theory you can but it cannot just be on whim or a want. There has to be a valid reason behind the request to do so. I have never heard of it happening but anything is possible.