(CNN) -- Flying JetBlue Airways? You might have to wait until your flight crew rests up if your travel includes Boston's Logan International Airport or the three New York City-area airports.
Blaming a weekend of bad winter weather and new Federal Aviation Administration rules on pilot duty times, JetBlue canceled nearly all operations from Monday afternoon into Tuesday morning at Logan, New York's John F. Kennedy International and LaGuardia airports, and Newark Liberty International Airport in New Jersey.
JetBlue, the only airline to say publicly that the new pilot rest rules contributed to its cancellation of flights during this week's winter blast, had asked regulators for a delay in implementing the changes.
FAA spokeswoman Laura Brown said that JetBlue last year requested an extension to the January 4, 2014, implementation deadline.
JetBlue was the only airline to request an extension, she said. The FAA denied the airline's request.
On Tuesday morning, JetBlue planned to ramp up operations to about 25% of its regular schedule and expected to become 100% operational by 3 p.m. ET, according to JetBlue spokesman Anders Lindstrom.
Lindstrom said Tuesday that the new scheduling rules related to pilot rest time "are a factor, not a driver, in our recovery from two winter storms and JFK infrastructure issues."
Statements from the airline on Monday suggested the pilot rules were a bigger factor in the carrier's near-halt in the Northeast.
While saying JetBlue was prepared for the new rules that increase rest requirements for pilots, scheduling pilots and crews is a "delicate" operation under normal circumstances, spokeswoman Tamara Young wrote via e-mail. "Delays or cancellations disrupt those handoffs placing crews or planes 'out of position' for their flights."
"In the midst of us repairing those schedules disrupted by this week's winter storms, we're facing an additional challenge as new FAA rules went into effect for crew rest," she wrote. "These rules further impact our ability to operate an already disrupted schedule, causing our pilots to 'time out' even sooner. As a result, additional cancellations are likely to occur as we work to reset the operation."
More than 400 JetBlue flights were canceled Monday, with 120 flight cancellations on Tuesday, the airline said.
Nationwide, more than 4,500 flights were canceled Monday, and more than 2,300 flights have been canceled for Tuesday, according to flight tracking site FlightAware.com.
JetBlue said it is scheduling extra flights to address the backlog and will extend apologies and compensation offers to passengers. Passengers whose flights have been canceled should not go to the airport, the airline said. The airline has compiled its advice to stranded passengers in a blog post, with links to the fee waiver policy and rebooking page.
The FAA announced the pilot changes in December 2011, and they went into effect Saturday. Pilot fatigue became a top priority for the Department of Transportation, which oversees the FAA, after the February 2009 crash of Colgan Air Flight 3407 near Buffalo, New York. The new rules require a minimum 10-hour rest period for pilots before their flight duty period, which can range from nine to 14 hours, depending on the start time and the number of flight segments and time zones crossed.
While other U.S. airlines are delaying and canceling thousands of flights because of severe weather patterns, no other major U.S. airline contacted by CNN has cited the new rules as a cause.
An airline pilots union said the airlines had sufficient time to adjust to the new FAA work rules.
"They had two years to anticipate this (work hour rule) and to adjust accordingly," said Sean Cassidy, vice president of the Air Line Pilots Association. "So I think it's overly simplistic to suggest that they could ascribe this disruption -- which happens to coincide with this major, major winter snowstorm -- and just hang it all on that rule-making change."
While the new pilot rest rules may be one of the many things that have disrupted air travel this week, ThePointsGuy.com's Brian Kelly said the airlines are looking to blame others for not hiring enough pilots to withstand disruptions to their schedules.
"The rules are necessary for passenger safety, (and) the airlines have had years to prepare," he said.
At the end of the day, "the airlines really can't withstand irregular events like these," Kelly said. "They have really bad emergency management plans in place."
CNN's Mike Ahlers and Aaron Cooper contributed to this report.