I know what you mean - our los are about the same age, and we having developmental wakings as well. A few nights ago DS was actually ASLEEP sitting up in his crib.
We've been up at least twice a night recently to lay him back down again from either standing or sitting. I've found that he usually does the best on days where he does very little else besides practice. Booooring I know but it works! The quicker they master the skill, the sooner they don't need to practice.
I know what you mean about the moaning and not wanting comfort too. My DS is a very noisy sleeper and it took me a long time to tell when he's actually awake and when he's not, or when he's awake but working on going back to sleep. He would get mad at me when I would try and help him - turned out I was only interfering! So, if he's showing you those signs, then leave him be. It's annoying I know, but he won't learn to self-soothe otherwise.