The bus to the airport is becoming increasingly popular. Today we had to go in to meet friends and by Los Tilos the bus was full. There was a drop off at Parque Tropical but apart from that the bus went non stop to Vecindario where lots got off.
Anyone hoping to catch it at San Agustin or Bahia Feliz was out of luck - and there were a few - and I am not sure that even all who wanted to get on at Los Tilos opposite the Yumbo managed it.
My point is that you should leave plenty of time or be prepared to take a taxi after all.
The bus in the evening on the way home was full except for one seat so a scramble and frayed nerves for boarding passengers.