Two of American Airlines’ largest workforces are looking to get a head start on negotiations for their next contracts, with unions representing pilots and flight attendants triggering early opener clauses to initiate talks in December and January.

The requests set up a critical stretch for American as it negotiates a new round of contracts outside the shadow of its 2011 bankruptcy and 2013 merger with US Airways.

Since the start of 2014 American has seen a record run of profits totaling $16.2 billion. The carrier will have to balance higher employee wages and benefits with rising costs.

Leaders from the Allied Pilots Association, which represents 15,000 American pilots, delivered a letter to the company’s headquarters Monday formally requesting the start of negotiations a year before its contract becomes amendable in January 2020.

The Association of Professional Flight Attendants, which represents 27,000 American flight attendants and whose contract becomes amendable in December 2019, made a similar request this month.

Of particular focus for the unions will be work rules affecting scheduling, sick leave and hotel accommodations on layovers.

American’s pilots and flight attendants raised concerns in recent months about scheduling policies.

Pilots have questioned increasingly frequent changes to their set schedules.

The pilots union said the schedule changes — which are allowed under the current contract — are causing pilot fatigue.

Monday’s announcement by the Allied Pilots Association cited “improved schedule integrity” as one of the union’s top wishes in a new contract.

“We believe American Airlines can do better. We believe American Airlines can be better,” union president Dan Carey said in a statement.

Flight attendants have been grappling with scheduling issues following the integration of pre-merger American and US Airways onto a single operating platform in October. While the move is meant to improve scheduling flexibility and efficiency for American and the flight attendants, the union said the rollout has been hampered by problems.

The group held a picket Sunday at Dallas/Fort Worth International Airport and other airports around the country to call attention to the scheduling problems, a new sick leave policy and other issues.

“One of the big problems is the (technology) and the programming for the new systems that have been introduced are not working. It’s violating our contract and our seniority,” union president Lori Bassani said last week.

Under federal law, airline employee contracts don’t expire but become amendable on a given date, at which point new terms can be put into place. Employees continue to work under the terms of the existing agreement until a deal can be reached, a process that can stretch on for years. More than 30,000 American mechanics and fleet service workers have been negotiating for a new post-merger contract since 2015.

Midcontract adjustments are rare, although American has handed out raises to pilots, flight attendants and others outside the typical negotiating process in recent years to bring their pay in line with competitors. The company reinstated profit-sharing in 2016, although the unions have pointed out the rates trail other airlines, making it a likely subject to be discussed in the upcoming negotiations.

For now, American’s pilots say they’re optimistic a new deal can be reached quickly.

“We fully intend to conclude these negotiations in months, not years,” Carey said. “The sooner we reach an agreement, the better for all concerned, including our pilots, our investors, and the passengers we serve.”