Frontier's Future With Spirit Airlines Remains Up In The Air Until At Least End Of June

(CBS4) -- Spirit Airlines is planning to decide its future by the end of June. The company says its board will choose which airline will acquire the discount airline before its June 30 shareholders meeting.

Originally, Spirit planned to merge with fellow budget and Colorado-based airline Frontier.

But recently, JetBlue sweetened its bid and offered Spirit's shareholders $31 to $50 per share in cash. That's up from $30 per share.

If regulators blocked the deal, JetBlue offered $350 million of a "break-up fee." Frontier had offered $250 million.

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