The girl I am almost done potty training is a notorious after nap pooper, so I always make her sit for a good length of time after nap and 90% of the time she poops. She is getting good at peeing on the potty without being prompted, but catching the poops is still a problem for her. If I knew that a child that I was potty training always pooped in the morning I would make it part of the daily routine to have them try during that time. Give them some books to look at (or something) and have them sit for awhile so they can relax their body and let it come out.

But yes, I also agree that the pull ups need to go if you have been going at it for 5 months already. He needs a push to have a reason not to just go in his pants.