There is ample time for that to happen for the new Embraer jets, but less so for the MRJ, which Mitsubishi plans to begin delivering to Trans States in 2016 and to SkyWest in 2017. Embraer does not plan to start delivery of its E175-E2 to SkyWest—or any other customer—until 2020.
Collective bargaining agreements with pilots become amendable at Delta Air Lines at the end of 2015, at United Airlines in early 2017 and American Airlines at the beginning of 2019. US Airways pilots are still working under a contract that became amendable years ago, and will negotiate a new joint collective bargaining agreement alongside American pilots if those carriers merge.
Airline managements and unions do not necessarily need to wait for contracts to become amendable; they often negotiate interim letters of agreement on specific issues. But scope is a very contentious issue for pilots, and they likely would not relax it easily, or without receiving some benefit in exchange.
Asked about the MRJ90 and E175-E2 exceeding the MTOW limits, Gregg Overman, a spokesman for the Allied Pilots Association, which represents American's pilots, said American can operate them as mainline aircraft flown by mainline pilots.
“Our take on that is that it would make a fabulous American Airlines airplane,” he says. “Any aircraft that exceeds 76 seats or that MTOW, if they're generating revenue for the company, they belong on the property.”