My LO was exactly like yours always using the left hand early on. I thought it was interesting because no one in my family is left handed. Then as he started to get some toys I noticed that he would adapt.
This is his favorite toy
and he had a hard time using his left hand to put the people in the slot, so he would pick up the little topsy tumbler guy with his left hand and then place it in his right hand and use his right hand to place the topsy tumbler in the slot
Now at a year he seams very ambidextrous. When I told his Dad how weird I thought it was because no one in my family was left handed and So is not left handed he said... Well all my brothers are left handed and my Dad is ambidextrous.
So I don't know what will happen in more time, LO is a year old now