Grats. Usually when you switch to rats, you will see the snake take off in growth for a bit, then they level out again.

As for rats being addictive to snakes, ive never heard that. Food is addictive to snakes be it rats, mice, rabbits, quails, chicks or guinea pigs. All of my snakes would eat 24/7 if i gave them the chance. Heck my Salmon boy struck the cage door the day after he got his adult mouse and tracked me like a champ as i was spot cleaning my dumerils cage below his. A healthy snake will always be hungry, doesnt mean it should eat all the time. Just like human kids love candy, doesnt mean they should eat it 24/7 lol.