I would consider Andrew to have been potty trained for "#1" by age 2.5. I recall this not because I was documenting things in a timely manner, but because he was precisely 2.5 when Margaret was born and I remember being barely confident that when he visited me in the hospital, he would be able to tell me if needed to go to potty. Since he had previously gone "#2" right after breakfast, I thought that piece of training was going to be a piece of cake. If it was predictable each day, surely that would make this easy! But, no. He promptly "reprogrammed" himself to wait for when he had a diaper on...either nap time or first thing in the morning. I knew we were in trouble when he would go in his naptime diaper not 5 minutes after having it put on:(
In typical first parent fashion, we diligently worked to encourage going poopy on the potty. We tried pulling the diaper for nap. He went in his underpants...and didn't call for us to let us know. We tried pulling the underpants. He went in his bed and laid there with it until after naptime. Lovely! Then we gave up, thinking "Fine! If you want poop in your pants, then knock yourself out! We'll worry about this if it's still an issue before Kindergarten.". That is the kind of mellowing that you will do once #2 is in the house. Thank you, Margaret!
By 3+, I was over diapers (the size 5 ones, anyway). So we hit it hard again that summer. One glorious July afternoon, Daddy and Andrew called Mommy at work to say, ‘I went poopy on the potty and Margaret is standing up! Can you believe it?’ All the waiting was worth every minute of this priceless, unsolicited quote:)