Waking up to a bottle is no where near as damaging in terms of tooth decay as going to sleep with one. As for drinking from a bottle once a day, I have a hard time believing that would push his teeth forward. My son is 5, and I still bring a sippy cup of milk to his room when he wakes up.
I wanted to mention that my friend's little girl went to the dentist at age three, and the dentist asked if she was using a bottle still. She wasn't. He said her teeth were being pushed forward, probably by the sippy cup, so a sippy cup could still do damage.
If you are worried go see a pediatric dentist. I waited until my son was 3, and he had 2 cavities, even though we brushed every night from when he was 1, and started flossing early as well. We suspect it was all those chewy fruit snacks we were giving him. Now we treat them the same as candy. He can occasionally have it, but only in the evening, shortly before teeth brushing. Our dentist suggested an exam for my younger daughter when she was a year old, and I understand that this is recommended. They can spot issues earlier that way.