I am flying to the US on Monday, initially it had only meant to be a 6 week stay. But no I expect it to be the full 90 days or slightly less. My ESTA has already been approved, so do I need to change my return flight now before departure, or can I change it once I am within the US.?
Simply what I am asking is, Can I stay in the US for up to 90 days, or will my flight schedule dictate how long I can stay in the US?