American Airlines and JetBlue have confirmed that their Northeast-focused alliance will launch as planned after a regulatory review.As part of the strategic pact, the two carriers will offer a host of passenger-focused benefits to create a seamless travel experience. For one, the carriers will align their Northeast networks, both in the New York and Boston metropolitan areas.Want more airline-specific news? Sign up for TPG’s free new biweekly Aviation newsletter!American will upgauge its domestic aircraft flying to and from New York to ensure that all routes are operated with a first-class cabin by the end of 2021. This means that the carrier will no longer fly the Embraer 140/145 to the New York area.Additionally, the two carriers will begin coordinating schedules in the first half of the year, delivering more flight options and connectivity across the two airlines.JetBlue will boost its presence at both New York LaGuardia and Newark, with up to 70 daily flights at the latter airport. The carrier plans to reactivate parked aircraft to fuel the expansion.American Airlines will add two new long-haul flights from New York-JFK; one to Athens (ATH) and another to Tel Aviv (TLV). Those were previously announced as part of plans for the partnership, with American chief revenue officer Vasu Raja saying Tuesday that they “are just two of many new routes we plan to launch.”During the first quarter, both American and JetBlue will begin codesharing on a variety of flights in the New York and Boston area. AA will add its code on more than 130 JetBlue routes, and JetBlue will place its code on more than 60 American routes. It remains to be seen which routes will be included in the pact.Flights that include segments in New York or Boston will be bookable both on jetblue.com and aa.com in the coming weeks.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.Perhaps most excitingly, the two carriers confirmed that reciprocal mileage earning and burning will be included in the alliance. Later this year, frequent flyers will be able to use JetBlue TrueBlue points for AA flights, and vice versa.More: Here’s how American and JetBlue should team up to reward frequent flyersAA and JetBlue teamed up once before in 2010. Back then, you could only earn redeemable miles for flights booked as part of the agreement. This time, the partnership will also cover point redemptions, but the carriers haven’t yet revealed award charts or earning rates for partner flying.The airlines have promised more details about how they’ll recognize partner elites, with an update expected to come later. In November, American and Alaska outlined reciprocal elite benefits, including upgrades on both airlines. Fingers crossed that American and JetBlue do the same.As part of the tie-up, the two carriers needed to make some concessions to the Department of Transportation (DOT) in exchange for the agency’s approval. This includes commitments to growth, slot divestitures at the capacity-controlled airports of New York-JFK and Washington/National (DCA) and other antitrust compliance measures.American and JetBlue have also promised that they will refrain from coordinating in markets where they compete head-to-head without significant competition from other airlines.One such market is South Florida.In the coming months, the new allies will begin competing in both Fort Lauderdale and Miami.As part of JetBlue’s latest 24-route expansion, the carrier will begin flying to Miami, a city that it’s long avoided due to the high operating costs at the airport. American Airlines, which operates a fortress hub in Miami, will compete directly with JetBlue’s four new MIA routes: New York-JFK, Newark, Boston and Los Angeles.American responded aggressively to JetBlue’s move with three new routes from Fort Lauderdale (FLL), a major focus city for the New York-based carrier. AA’s flights to New York-JFK, Boston and Los Angeles begin in April.Nonetheless, the Northeast-focused alliance is on, even if the new allies compete fiercely in other markets.