Pooping Finally... Standing up?

Yes, that's right Travis is pooping but he is pooping standing up on the toilet. He had always tried to go sitting on his little potty, but wouldn't sit on the toilet until I bought the seat to go on top. Then lately he wouldn't even sit down anymore. When he wanted to try standing up I told him no and made him sit... this just led to him not pooping for two days. So he finally said he had to go poop again, but wanted to stand again... this time I decided to let him try standing up. Well, he did it! I was just happy he finally pooped in the potty, I didn't care how it got there... yet I must say it was quite the scene. So this happened on June 20th... and today we are still pooping standing up, he still won't sit but I am determined to get him to before preschool?