Meaning of 'no earlier than X days after Y'

I am having trouble understanding the following notice on the American Airlines AAdvantage (miles account) website:

Note: Mileage credit requests can be submitted no earlier than 15 days after all travel is completed.

What does it exactly mean? Which of the following statements is the correct interpretation?

1. I have to wait for 15 days after all my travel is completed before I can request my mileage credit
2. If I want to request my mileage credit, I have to do so within 15 days after my travel is completed
3. Something else

In any case, I wonder, is the original statement grammatically correct?

The statement

Mileage credit requests can be submitted no earlier than 15 days after all travel is completed

means you must wait for 15 days to do the submission and cannot do it earlier.

The statement

Mileage credit requests can be submitted no later than 15 days after all travel is completed

means you must do the submission within 15 days and cannot do it later.

Both statements here are grammatically correct (and mean different things).