23.S.11 of the PWA. There is an example in there. 2 AM is wrong, old airline, wrong contract.
11. A reserve pilot who flies on an X-day due to an IA, GS or reroute will be given nine
hours free of duty upon his release at the completion of his rotation.
a. His X-day(s) will begin immediately following such nine-hour period and will
continue until he has received a period of 24 hours free of duty for each interrupted
and remaining X-day in his scheduled X-day block.
b. If the remaining days in the bid period are insufficient to contain the X-day(s), the
pilot will be granted an additional day(s) off under Section 23 S. 16.
Basically since you were flown in to an off day, your off day will start after nine hrs of rest and then you will get that credited on the back end of your off days. At least that is how I read it.