By For most travelers, the prolonged grounding of the beleaguered Boeing 737 Max has been a nuisance.Repeated flight changes and cancellations, the latest announced last week by Southwest, United and American, have messed with travel plans.For California frequent flyer Carlos Burgos, the nearly yearlong string of schedule changes has been a bonanza, allowing him to save money and time on multiple Southwest flights."It's been the best thing in the world,'' he said.Burgos and other savvy travelers have taken advantage of Southwest's generous flight-change policy during each Max flight schedule change.Read more on NewsOK.com