The abrupt cancellation of 30 Swoop flights over the first 10 days in July sparked anger and confusion, with some customers paying out-of-pocket to salvage travel plans.

New federal air passenger protection regulations, which roll out Monday, aim to cut down on customer confusion by laying out clear compensation amounts and treatment standards for mishaps involving all airlines. But rules covering cancelled and delayed flights won't take effect until December. The regulations also face two legal battles, including one from airlines trying to quash them in court.

In the meantime, upset Swoop passengers haved launched their own battles. So far this month, the Canadian Transportation Agency has received 19 complaints concerning cancelled Swoop flights.

The ultra-low-cost-carrier, which is owned by WestJet, said the cancellations were caused by unscheduled aircraft maintenance.

"Safety is our number one priority," said Swoop spokesperson Karen McIsaac in an email. "We are deeply sorry for the inconvenience and disappointment we have caused and continue to direct our efforts to assisting those travellers that have been affected."

Yeah seriously. Call centre closed on the day they cancel flights. Only options are to accept the rebook or cancel outright. How about <a href="https://twitter.com/FlySwoop?ref_src=twsrc%5Etfw">@FlySwoop</a> find everyone flights to get us home when they said they would. —@froggerlax

Radek Romanowski got his cancellation notice the evening before his July 8 return flight from Fort Lauderdale, Fla., to Hamilton. A second email that night informed him that he was rebooked to fly on July 15 — one week later.

That didn't work for the small business owner who needed to return home to Komoka, Ont., for work. But he couldn't call Swoop to complain — because it was Sunday and the call centre was closed. He did send an email, but received no reply.

"It's very, very bad business practice," said Romanowski. "No communication, no conversation, no answering, nothing."

In desperation, his wife, Hanna, used up more than 22,000 Aeroplan rewards miles to rebook him on an Air Canada flight the next day.

"It should be better back-up or better service to get people back to where they are going," she said.

When Radek Romanowki's Swoop flight was cancelled, his wife, Hanna, spent more than 22,000 Aeroplan rewards miles to get him back home quickly to Komoka, Ont. (Submitted by Hanna Romanowki)

Kevin Blenkhorn found out his Swoop flight was cancelled when he and his wife showed up at the Hamilton airport on July 7 to take their return flight to Edmonton.

"I was not happy," said Blenkhorn who lives in Fort Saskatchewan, Alta. Swoop had rebooked him on a flight that departed six days later, but Blenkhorn needed to get home immediately to return to his mining job.

He found a flight leaving the next morning on WestJet — Swoop's owner — totalling $1,462 for two last-minute tickets. He was surprised that WestJet wouldn't waive the cost.

"I called WestJet and they said, 'Well, we really don't have anything to do with [Swoop].'"

Kevin and Brenda Blenkhorn of Fort Sasktachewan, Alta., flew on Swoop to attend a golf tournament in Ontario. They found out at the airport that their return flight was cancelled. (Submitted by Kevin Blenkhorn)

Blenkhorn's new booking cost him close to triple the price of his yet-to-be refunded Swoop tickets. Following the advice of a Swoop employee at the airport, he filed a claim with the airline, requesting reimbursement.

"Til the money's in the bank, I'm not counting on anything," he said.

What does Swoop owe passengers?

CBC News interviewed a total of four affected Swoop customers who each said they were unhappy with what was offered: a refund or a rebooking on a Swoop flight on a later date. Those are also the only options the airline publicly listed in tweets to complaining passengers.

However, for flight cancellations within its control, the airline's current rule book — or tariffs — also lists another alternative: rebooking passengers on a different airline "in situations where other options have been deemed unacceptable."

Travellers are being rebooked on the next available Swoop flight. If the alternate flight time provided is not suitable, travellers are able to self-manage bookings at <a href="https://t.co/DdTLlCGNpH">https://t.co/DdTLlCGNpH</a> or cancel for a full refund. ^KS 2/2 —@FlySwoop

CBC asked Swoop why many passengers weren't also offered a rebooking on another airline.

"We are following what is stated in our tariffs," said spokesperson McIsaac on Tuesday. "After rebooking on the next available Swoop flight, we are working on a case-by-case basis with travellers on alternate arrangements if the new flight time provided is not suitable."

Consumer advocate John Lawford said — based on Swoop's written rules — it could be left open to interpretation when precisely it had to offer affected passengers seats on another airline.

He believes Canada's new air passenger regulations will help cut through the ambiguity.

"This whole thing is set up to be consumer friendly, easy to understand, consistent, transparent," said Lawford, executive director of the Ottawa-based Public Interest Advocacy Centre.

However, some critics say the regulations aren't tough enough because, among other complaints, passengers on "small" airlines have fewer rights.

For example, the rules allow small carriers — such as Swoop — to pay out lower compensation and offer fewer travel options when flights are cancelled.

But Lawford said at least passengers will be able to easily access all the rules before they choose an airline, and make their decision accordingly.

Court battle takes flight

The air passenger protection regulations also face a couple of legal challenges.

On June 2, 17 applicants — including Air Canada, Porter Airlines and the International Air Transport Association — argued in a Federal Court of Appeal filing that the regulations are "invalid" because they contravene international standards.

Lawford said the new rules will still roll out Monday. But he fears some airlines may refuse to comply while the case is before the courts.

"They'll hide behind their lawsuit."

All of Canada's major airlines, including Air Canada and Porter told CBC News they will comply with the current rules.

Disability rights advocate Bob Brown and passenger rights advocate Gabor Lukacs have also filed an application with Federal Court of Appeal, challenging the regulations.

They claim rules allowing tarmac delays of close to four hours violate the charter rights as some people with disabilities may not be able to tolerate such a long delay. They also argue the regulations take away some existing protections for "bumped" passengers.