The powerhouse alliance between American Airlines and JetBlue continues to spread its wings in the Northeast.On Tuesday, the two carriers unveiled the next phase of their Northeast Alliance, designed to boost connectivity in the New York and Boston markets, with added routes, enhanced coordination and more.Though Tuesday’s update summarizes much of the previously announced growth, there are some interesting updates coming in the weeks and months ahead.Want more airline-specific news? Sign up for TPG’s free new biweekly Aviation newsletter!JetBlue’s 12 new routes get a start dateIn April, JetBlue shared plans to add seven new cities and two new countries, with 17 routes throughout the rest of 2021 and into 2022.On Tuesday, the New York-based carrier announced launch details for a handful of these markets, with the specifics in the table below.DestinationOrigin(s)Launch detailsSan Antonio (SAT)Boston (BOS), New York-JFK1x daily begins on Oct. 31Puerto Vallarta, Mexico (PVR)New York-JFK1x daily begins Feb. 19, 2022Kansas City (MCI)Boston (BOS), New York-JFK1x daily on each route begins on March 27, 2022Milwaukee (MKE)Boston (BOS), New York-JFK1x daily on each route begins on March 27, 2022Jacksonville (JAX)New York LaGuardia (LGA)2x daily begins on Oct. 31Sarasota-Bradenton (SRQ)New York LaGuardia (LGA)1x daily begins on Oct. 31. (Note this is winter seasonal)Savannah (SAV)New York LaGuardia (LGA)1x daily begins on Oct. 31New Orleans (MSY)New York LaGuardia (LGA)1x daily begins on March 27, 2022Nashville (BNA)New York LaGuardia (LGA)2x daily begins on March 27, 2022Notably, flights to Kansas City and Milwaukee, as well as select frequencies to San Antonio, will be operated by JetBlue’s newest domestic workhorse, the modern Airbus A220-300, which the carrier inaugurated in April. This 140-seat plane is designed to replace the aging Embraer 190 fleet, and offers an upgraded inflight experience, with larger TVs, faster Wi-Fi and more.The remainder of the flights will be operated by Airbus A320 family aircraft.JetBlue notes that the number of daily frequencies on some of the new routes is expected to increase in the future, but no details are available yet. By the end of 2021, JetBlue plans to offer 35 daily departures at LaGuardia and intends to grow to more than 50 daily departures by summer 2022.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.The latest announcement leaves just five previously announced routes with no official start date yet. This includes the airline’s first-ever service to Canada and Honduras. For reference, you’ll find the remaining new JetBlue routes listed below.DestinationOrigin(s)Launch detailsSan Pedro Sula, Honduras (SAP)New York-JFKDecember 2021Vancouver (YVR)Boston (BOS) – Seasonal, New York-JFKSummer 2022Asheville, North Carolina (AVL)Boston (BOS) – SeasonalSummer 2022Portland, Maine (PWM)New York LaGuardia (LGA)Summer 2022Goodbye to the convenience of LaGuardiaJetBlue is packing its bag at LaGuardia’s Marine Air Terminal. In the months ahead, the airline will begin vacating its current terminal at LaGuardia and move into the airport’s newly opened Terminal B.The Marine Air Terminal is one of the most convenient at LGA. It’s accessed via a dedicated exit from the highway and doesn’t suffer from the same road congestion as LaGuardia’s other terminals. With just six gates, it almost feels like you’re flying private.Many JetBlue flyers will miss the ease of flying from Terminal A, even though it lacks some basic conveniences, like a variety of concessions and dining options.By relocating to Terminal B, JetBlue can offer more seamless connections with American Airlines. AA already occupies a portion of the terminal’s Western Concourse, and as more gates are built there in the coming months, JetBlue will be able to easily relocate its existing operation.Also, JetBlue flyers will soon have easy access to the new Amex Centurion Lounge in Terminal B once the airline officially moves.Meanwhile, at New York-JFK, the two carriers are going to stick to their homes — Terminal 5 for JetBlue and Terminal 8 for American — but the airlines have added a shuttle bus that’s available post-security for easier connections.Reciprocal loyalty benefits are (finally) comingWhile you can now accrue miles on both AA and JetBlue flights, you can’t yet redeem them for either carrier nor can you enjoy your elite status perks when flying on a flight operated under the Northeast Alliance.That’ll change this fall when AAdvantage elites and TrueBlue Mosaic members will start receiving benefits when flying on either carrier.While the details are still light, the airlines unfortunately didn’t mention anything about upgrades or lounge access as a reciprocal benefit. Instead, the carriers shared that benefits will include priority check-in, security and boarding, plus up to two complimentary checked bags.The lie-flat wars are getting hotterThough the real news of Tuesday’s announcement is the start date for JetBlue’s new routes, the airlines buried the lede.Instead of first writing about the launch details in the press release, the airlines decided to instead focus on the premium transcon network that’s enabled by the Northeast Alliance.AA’s Flagship Business on the Airbus A321T (Photo by Zach Griff/The Points Guy)It goes to show how important these lie-flat routes are to the recovery from the pandemic. The airlines are likely trying to woo deep-pocketed leisure travelers, as well as corporate accounts, to choose them for the top-notch experience offered on cross-country routes.To that end, all transcontinental routes operated under the Northeast Alliance will feature lie-flat seats in the pointy end of the plane in 2022. The full list of routes, with the product(s) offered, is listed in the chart below.DestinationOriginProduct offeredAircraftLos Angeles (LAX)Boston (BOS)American Flagship First, Flagship Business, JetBlue MintAA Airbus A321T, JetBlue Airbus A321 with MintLos Angeles (LAX)Newark (EWR)JetBlue MintJetBlue Airbus A321 with MintLos Angeles (LAX)New York-JFKAmerican Flagship First, Flagship Business, JetBlue MintAA Airbus A321T, JetBlue Airbus A321 with MintOrange County (SNA)New York-JFKAmerican Flagship First, Flagship BusinessAA Airbus A321TSan Diego (SAN)Boston (BOS)JetBlue MintJetBlue Airbus A321 with MintSan Diego (SAN)New York-JFKJetBlue MintJetBlue Airbus A321 with MintSan Francisco (SFO)Boston (BOS)JetBlue MintJetBlue Airbus A321 with MintSan Francisco (SFO)Newark (EWR)JetBlue MintJetBlue Airbus A321 with MintSan Francisco (SFO)New York-JFKAmerican Flagship First, Flagship Business, JetBlue MintAA Airbus A321T, JetBlue Airbus A321 with MintSeattle (SEA)Boston (BOS)JetBlue MintJetBlue Airbus A321 with MintSeattle (SEA)New York-JFKJetBlue MintJetBlue Airbus A321 with MintBottom lineAmerican Airlines and JetBlue are charging ahead with their nascent Northeast Alliance. This winter, the airlines will offer more than 700 daily flights, with 57 new markets and more than 110 codeshare routes from Boston and New York.But it’s not just about an expanded network.The airlines are moving forward with plans to enhance their frequent flyer partnership as well as the on-the-ground connection experience.It’ll be interesting to follow how the alliance continues growing, especially as other airlines begin retaliating.