[SAinthe21stC]

While it is disappointing to hear this news. Aside from Air Canada's flight, the rest of the cancellations are coming from Frontier Airlines which won't occur until later this year.
Frontier's cancellations are happening to dozens of other cities across the country including Austin, San Jose and Cincinnati.
The second thing to note is that most of the destinations are seasonal, infrequently serviced routes for mostly leisure travelers.
From reading recent articles on this news it is noted that SAT officials aren't overly worried for a number of reasons including only losing about 1.5% seating capacity of total capacity from these flights.
They are already working on other options to Canada and recouping some of the destinations serviced by Frontier with other airlines and should continue to announce news flights/routes during 2019. SAT will continue to passenger growth records broken and I cannot wait until they finalize expansion details at least for the short-term to most likely open another terminal before 2023 among other details.