Last Tuesday, Allegiant Air announced that it was adding seasonal service between St. Cloud and Orlando. To spur bookings, the airline offered a $99 round-trip special to customers who made arrangements within three days.

That was just the kind of deal Cyndy Chancellor was seeking to get six people to sunny Florida for a week in February. Unfortunately, she didn't get the deal.

Chancellor acted on the first day of the three-day promotional period. She went to the airline's website and could not find the sale. When she called, Chancellor was placed on hold for 35 minutes. Finally, when an agent did come on the line, she told Chancellor that she could not find the advertised fare, but that there was one for $89 per person each way.

Chancellor e-mailed the airline's reservation's center and eight hours later got a reply saying that Allegiant works on a tier system, "which is to say we have [only] so many tickets available at a certain price. Once those lower-price tickets are sold, then ticket prices will go up to the next price level. These fares are fast selling and may not always be available for your dates of travel. Please be advised that our airfares are subject to fluctuate at any time and may occur during the booking process."

By then the good deals — the few that were available — were long gone.

In a news release, Allegiant does have a disclaimer that says "seats are limited," and, boy, are they ever.

An airline spokesman told The Drive that roughly 10 percent of available seats were set aside for the promotion. Allegiant will fly MD-80s twice weekly between St. Cloud and Orlando. The planes have room for 166 passengers, meaning about 16 seats per flight qualify for the low rate. Allegiant, which says it's "known for its exceptional travel deals," has 39 departures during the promotional period, which allows customers to book travel between Dec. 18 and April. 29.

The Drive did some checking on Wednesday — the day after Chancellor tried. The Drive was unsuccessful in finding anything close to the $99 round trip. The best it could do was a departure on Jan. 9 for $85 and a return trip on April 9 at $45.

"We like to bring a lot of attention to the new route," said Mike Lillard, a spokesman for the Las Vegas-based airline. "They often sell out within the first 24 hours. They are very limited in nature for each flight. Once they are sold out, they go away whether we hit the cutoff date or not. We see the highest number of bookings within the first 24 hours."

Marlyn Schmitz, of Princeton, and a handful of other readers said they were stymied with the reservation process. Many expressed exasperation with long wait times and the difficulty of finding a phone number on the airline's website (1-702-505-8888, www.allegiantair.com).

"I guess it was too good to be true," Chancellor said.

Allegiant Air began serving St. Cloud last year with nonstop flights to Phoenix. It filled a void in St. Cloud since 2010 when Delta Air Lines stopped flying 34-seat prop planes between St. Cloud and Minneapolis-St. Paul International and Sun Country curtailed flights to gambling resorts in Nevada.

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