1: RPN can never be RN without university nursing degree.
2: The trend is: RPN is replacing RN because the new two year RPN program is similiar to the old RN program. Canada is and will be short of RN for a long long time. They have to hire more RPN and expand RPN's practice scope. They are doing so.
3: USA RN earns more than Canadian RN. That's one of the reason why Canada is short of nurses. Many young RNs are attracted to the States because of pay and benefits.