Kalitta is an ACMI operation and not any different than any other ACMI operation, Atlas, Southern, Polar, you name it. Bid a line? Yeah, you can bid a line and even have it awarded. But that does not mean you will fly anything resembling the line. Scheduling is always a constant shuffle sort of like putting fingers in a dyke to stop the leakage. Need a plane? Oh yeah we will get you one. Oops. no crew? No problem, we'll just grab the nearest crew off their line and back fill. The cost of buying an extra ticket for the back fill. Hey, that won't cost much when buying bucket list economy seats. Pilots don't need all that rest anyway. Oh those days off you are guaranteed? Dream on! We'll just take a few, you are making extra pay aren't you? And that jet lag? Eh, you will get over it.
That is the philosophy of ACMI. You are a slave to marketing who have no concept of crew rests or contracts.
I flew like that for 6 years and when I finally reached 60 I had to leave, my blood pressure dropped 20 points. It does get to you sooner or later.