Originally Posted by tennisguru

Anything on day 2 pays 50% of Block + Minutes Under. Every leg on day 3 pays 100%, plus any trip credit also pays 100%.

Any reroute that you receive but don't actually operate is irrelevant. All that matters is what your final rotation as flown looks like vs what your original rotation was scheduled. Just spitballing but assuming day 1 was just DTW-STL, I'd say L4 RRPY should be around 11-ish, maybe 12, somewhere in there. Basiically take 15:45, minus the block of DTW-STL and STL-ATL, minue 1/2 of ATL/BHM. That's roughly 3-3.5 hours total, so the rest is day 3 block and credit. L9 should be over 10. There is a scheduling alert (25 - 0 something) that lays out exatly how to calculate L4 using the archived rotation in icrew. Widgetcrew.com also has a paid subscription where you can just copy/paste and it'll walk through the pay, and there is a reroute app on the apple app store which will also do the math for you (can't remember if it's free or paid).