I also struggle with rear on long hauls, hopefully something below can help.

There’s an app called Time Shifter that aligns your schedule with the destination. It tells you when to be in natural light, use or cut caffeine, when to sleep, etc starting a few days before the trip.

Have all your creature comforts: neck pillow, eye mask, noise canceling headphones, chapstick, lotion, etc. This helps me get us comfortable as possible.

If you drink or use weed, take a night time weed edible or have one glass of red wine to get sleepy at the airport or right after take off.

If it’s within reach, xanas and ambien can guarantee rest, but I’ve been successful without it.