11 month old bedtime... nap question

I have an 11 month old boy. On my days off from work he usually goes to bed about 8:30 and sleeps till 9am. He does wake up to eat once in between this. During work days, my bf works 7-3, I work 6-6pm or am depending on the week. Yuck.

Anyways he wakes him up about 6am to get to babysitter at 6:30am. He doesn’t take a nap all day at the babysitter even though I wish he would cause the time he gets home about 3:30 he’s ready for a nap and needs a nap. Usually let him sleep till 5pm. Now that really messes with his bedtime cause he is not ready for bed at 8-9pm usually. So he only gets 8-9 hours of sleep when he really needs 12 or so. How would you do this? Not give him a nap after I pick him up? Babysitter says she cannot get him to take a nap even though I think she could. I won’t see him much the days I work since I work 12 hours and it sucks but just trying to make it easier on my bf when I work nights or both of us when we work days.