Vancouver - Seoul - Beijing - Seoul Qualify?

Our start of flight is Vancouver (Dec 17) to Beijing (Dec 18) then later to Seoul (Dec 21)
But from Vancouver we land in Seoul first for 90min layover than transfer for flight to Beijing ( Dec 18) for our stay of 4days before going to Seoul (Dec 21). Does this qualify for 144h Visa free transit? Because the transfer to and from Seoul Korea is the same country of flight to Beijing, even though we started from Canada. Thank you for you help!