Is it common for shelters to lie and say a dog is younger than he is in order to improve them getting adopted?

I don't think they would lie about age. Some dogs are just more calm than others. At 8 months he should be already housebroken anyways. My pomeranian is. I don't think they would lie about his age. He a cute dog, he would have been adopted anyways. My pomeranian is almost 8 months, he is very calm compared to most adult pomeranians that I have seen. Every dog is just different.