Spirit Airlines Inc.’s shares soared the most in 13 years of trading after the carrier secured more time to address a troublesome debt load that has raised the prospect of bankruptcy.

Spirit Airlines (NYSE: SAVE) has secured more time to work out its debt burden, easing near-term bankruptcy fears. The stock took off on the news, trading up as much as 73% on Monday morning and up 58% as of 1 p.

Spirit Airlines’ stock swelled by 60% on Monday, on track for the low-cost airline’s best day since going public, after the carrier announced an extension to refinance its debt while temporarily avoiding the threat of bankruptcy.