To wait or get investigated now?

My son has white yellowish lumps under his tongue since he was born was referred to hospital they aren’t sure what they are could be oil glands dr advised and would need to go under general anaesthesia to get a sample he’s suggested waiting till baby is 2-3 years old but said he would do the op now if I wanted not sure what to do? Any ideas what these could be? Would you wait or get it investigated now? I asked if it could be harmful to wait and he just said well he’s had them a year and seems ok