A day after Canada joined countries around the world in closing off its airspace to Boeing's 737 Max 8 and 9 aircraft over safety concerns, the country's two top airlines are still struggling to reschedule flights and manage concerned customers.

WestJet and Air Canada operate 37 Max planes between them, with each aircraft making multiple trips a day.

So Transportation Minister Marc Garneau's announcement that Canada would ground the aircraft Wednesday triggered delays and cancellations affecting thousands of travellers.

A Max series plane was involved in an Ethiopian Airlines crash that left all 157 people onboard, including 18 Canadians, dead over the weekend.

The airlines have since been able to get some flights off the ground by swapping aircraft, but in some cases, flights have had to be cancelled.

"The only thing they could do was tell me to call Air Canada ticketing, which I did but I could not get through all night because of overwhelming calls. They had to shut off the phone services," said Angie Cheng, whose flight to Toronto was cancelled after she visited Vancouver for her grandmother's funeral.

Air Canada now has a dedicated phone line for those travelling in the next few days. Cheng was finally able to be re-booked on a flight leaving Friday.

In WestJet's case, the airline cancelled 11 flights across the country Thursday - including ones from Vancouver to Toronto and Vancouver to Calgary – leaving travellers like Dan Lin unable to get home.

"We’ve been up for over 48 hours. I've been trying to do the math, but my brain's not working," said Linn, who was trying to get home after a vacation in Thailand. "We've just had a flight cancelled here because of the 737 Max 8."

Both airlines have emphasized that Max aircraft only represent a small portion of their fleet, adding that they expect things to return to normal after the weekend.

In the meantime, Air Canada – which has been using Max aircraft for flights to places like Hawaii – is bringing in larger planes.

And passengers like Cathy MacDonald are hopeful they'll finally be able to make to their destinations.

"We've been looking forward to it for a year and we're going for 12 days," said Macdonald, who was scheduled for Maui Thursday morning, but had to wait until the evening to take off.

"It's not Air Canada's problem. It's a plane problem, so we were just lucky they were able to find a solution for their planes being shut down. We're lucky it's being handled in the same day and we didn't have to lose our vacation due to a plane malfunction."

It's not clear how long Transport Canada will keep Max planes on the ground, but anyone flying in the next few days is advised to keep checking in with their airline and be prepared for a change in their itinerary.

With files from CTV Vancouver's Ben Miljure