Can I change my sons bottles now?

My son suffered with severe colic and GERD since birth up until he was about 9 weeks old. He's almost 7 months old now, on the 27th, and I was wondering if I can change his bottles now? When they told me he had colic and GERD I bought him the Dr.Browns bottles for colic and he's been using them ever since. He doesn't have colic anymore and hasn't had it for a while now. My worry is if I change his bottles will he get it again? The Dr.Browns bottles come with the tube on the inside and it just takes way too long to wash them all on a daily basis. Thoughts and opinions please and thnak you!