for AA purchases, you only earn 1 LP toward status, the other 3 LPs are considered bonus and do not apply toward status. With AA credit cards, you get 1 LP for status and 1 LP as a bonus (not counted toward status). The Executive CC just raises the bonus from 1 LP to 3 LPs.

You will earn the LPs at time of ticket purchase. If you cancel the ticket, you still keep the LPs since you only get a flight credit and not cash back. It is a risky strategy since you would have only 1 year to use the flight credit from time of purchase and can not combine flight credits.