Passengers flying with Air Canada can breathe a sigh of relief after the airline reached a last-minute agreement with its pilots, narrowly averting a significant disruption that would have impacted more than 110,000 travelers per day.

The tentative four-year deal, struck in the early hours of Sunday, forestalled a potential strike or lockout that had been looming for weeks. Without the agreement, Air Canada had been prepared to gradually cancel flights before completely halting operations as early as 12:01 a.m. Eastern on Wednesday, September 18th.

The Air Line Pilots Association, representing over 5,200 Air Canada pilots, has been negotiating for the past 15 months, seeking wage increases and improvements in work rules. Air Canada’s pilots sought to close the pay gap with U.S. counterparts. U.S. pilot wages increased substantially over the past couple of years, though airline demand for pilots has since abated.

The pilot deal at Air Canada’s joint venture partner United paid cockpit crew in some cases nearly double what those at the Northern partner earned.

Air Canada initially offered a wage increase of over 30%, along with improvements to pension and health benefits. ALPA reported that some pilots had even taken on second jobs, but of course with around 80 hours of flying time per month on average pilots in the U.S. take on entire second careers too.

While details of the new agreement haven’t been announced, ALPA reports $1.4 billion in value over four years, representing a 46% increase compared to the previous contract.

Air Canada, the country’s largest airline, had already begun canceling cargo services, halting the acceptance of perishable goods, and laying out a wind-down plan for passenger operations. Looming in the background was potential government intervention to prevent cessation of operations.