I live in Athens Greece and am in the US on the ESTA. This is my first time in the US. My 90 days will expire soon. A friend of mine from Budapest claimed that he was able to go to Mexico for a few days "on vacation" and then was able to stay in the US for an additional 90 days. He also suggested keeping my current ticket to go back to the US and changing it once I return to the US (if I'm allowed back in). He said that they will stamp my passport since I will be "flying out in a few days" from the US. He says once I receive this stamp I will be allowed to stay for another 90 days.
I looked at my current stamp on my passport and it has a 90 day period of how long I can stay in the US.
If/when my passport is re-stamped and I am admitted back into the US, will there be dates of how long I may stay again?
Once your passport is stamped a second time do they always include the period of time you are allowed to stay?
For example if I come back into the US on December 28th and my (original) return flight is for December 30th will they stamp my passport for the two remaining days?