Spirit Airlines Inc.’s stock SAVE tumbled 4% in premarket trade Wednesday, after the discount carrier lowered its third-quarter guidance to reflect increased promotional activity for travel in the second half and aa recent spike in fuel prices. “During the last few weeks, the company has seen heightened promotional activity with steep discounting for travel booked for the second half of the third quarter through the pre-Thanksgiving travel period,” Spirit said in a regulatory filing. The airline is now expecting third-quarter revenue to range from $1.245 billion to $1.255 billion, down from prior guidance of $1.300 billion to $1.320 billion. It expects fuel cost per gallon of $3.06, up from prior guidance of $2.80. The company expects available seat miles to rise 13.4%, down from guidance of 13.7% previously. The news comes as JetBlue Airways Corp. JBLU makes concessions to attempt to get its mooted merger with Spirit back on regulatory track. Spirit’s stock has fallen 11% in the year to date, while the U.S. Global JETS ETF JETS has gained 8% and the S&P 500 SPX has gained 16.2%.

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