A reporter tried to use Frontier's $1,999 all-you-can-fly pass. It wasn't easy.

• Frontier Airlines sells an "all-you-can-fly" pass, which costs $1,999 for an entire year.
• The subscription offers unlimited travel throughout Frontier's network — if a seat is available.

Frontier Airlines' new "all-you-can-fly" GoWild Pass has officially taken off. While some have found it isn't always the easiest way to travel, it can pay off if you're flexible.

In June, Dawn Gilbertson, a reporter at The Wall Street Journal, used the Colorado-based carrier's new flight subscription, which markets unlimited travel to anywhere in Frontier's network.

She paid $599 for the pass, which was on sale at the time but goes for $1,999 now for an entire year. Seasonal passes for summer and winter are cheaper.

While the low price sounds like a steal, Gilbertson noted per-flight taxes, bags, and seats cost extra. Moreover, there are several caveats to "unlimited" travel.

These include the short time frame for booking: up to one day for domestic flights and 10 days for international, and pass holders can only reserve a seat if one is available.

This means weekend getaways can be difficult to plan without a confirmed return flight home, but those who have the flexibility and spontaneity — such as digital nomads — can really take advantage of the program.

According to Gilbertson's report, she took a total of seven GoWild flights from June 20 to June 28 and paid an average of $96 per leg.

Some of these were extremely last-minute, such as the very first flight from Phoenix to Atlanta booked a few hours before takeoff.

The price Gilbertson paid was $15, which was peanuts compared to Frontier's $369 last-minute fare for non-GoWild tickets. Delta Air Lines' was over two times as much at nearly $1,000 for the same route.

From Atlanta, she headed to the Dominican Republic for $73 and then to Chicago for $90. Like the first leg of the trip, both were much less than the regular same-day fares.

However, Chicago is where she hit a snag and realized that confirming GoWild seats can be difficult, mostly due to Frontier's lack of flight frequencies between many city pairs — especially to the Caribbean.

She tried places like St. Thomas and Puerto Rico with no success, so she headed to Orlando, Florida, hoping to connect to an island nation from there. However, there were still no GoWild tickets available. The only one open was to St. Maarten, but there wasn't a return flight until a week later.

Gilbertson ended up exploring Walt Disney World that day instead, and then headed to Hartford, Connecticut, via Raleigh to see family. The following day, she took three planes via Atlanta and San Diego home to Phoenix because it was the best GoWild route available.

During her travels, Gilbertson said she had plenty of wins, such as a riverfront lunch in Chicago, a day trip to Newport, Rhode Island from Connecticut, and fish and chips at Disney.

However, she also realized "unlimited" travel can be very limiting.

Passholders can't simply hop on any plane they want at any time. It's like piecing together a giant game of Tetris, but you're not only competing against other GoWild members for a seat — you're also battling potential weather delays and cancellations that could make it even more difficult to get to where you want to go.

Julia Carmel, a reporter for the Los Angeles Times, wrote about a similar experience in May, noting the high taxes for international flights.

Despite the challenges, there is a GoWild community already brewing on Facebook with over 9,000 members helping each other find the best routing options, as well as educating others on what to expect when actually using the pass.

"A lot of people jump to conclusions," Jacob Brown, a veteran GoWild pass holder, told the LA Times. "The first time they want to go somewhere and they look and a flight isn't available, they think it was a waste of money. The whole point of the pass was not to get guaranteed seats. It was for really quick getaways and last-minute flights."