Spirit Airlines Inc. is in talks with Frontier Group Holdings Inc. about filing for bankruptcy to facilitate a takeover by the rival discount carrier, according to people with knowledge of the matter.

After months of bankruptcy rumors growing increasingly louder, Spirit Airlines (SAVE) has been on a relative roll lately. The airline’s shares soared by as much as 73% after it managed to restructure its debt load in a way that would extend its payment deadlines until the end of December and give it the $1 billion in liquidity that will allow it to stay operational until at least the end of the year.