Spirit Airlines is facing financial struggles and is ending service in multiple U.S. cities this fall. Rivals like United Airlines are adding new flights in cities where Spirit operates to provide customers with alternative options in case Spirit shuts down. Spirit has shot back at these moves, emphasizing its commitment to providing low fares to consumers.

United Airlines is adding new flights starting Jan. 6 in cities where Spirit operates. Last week, Frontier Airlines announced 20 new routes that compete with Spirit. Spirit is exiting several cities in October and canceling plans for new service in Macon, Georgia. United is also adding more flights between various cities.

Analysts predict that full-service airlines will benefit from Spirit’s troubles. Larger airlines like Delta and United are improving their onboard products and expanding their networks to attract customers who may be looking for alternatives to low-cost carriers like Spirit. Spirit filed for its second Chapter 11 bankruptcy last week after facing weaker-than-expected demand and high costs.

Upon filing for bankruptcy, Spirit announced plans to scale down its network and shrink its fleet to reduce costs. The airline did not make deep cuts during its first bankruptcy filing, but is now facing tough decisions to improve its financial situation. Spirit warned earlier in August that it might not survive a year without increasing its cash reserves.

Read more at CNBC: Spirit Airlines cuts flights in 12 cities as United, rivals circle