Jetstar has been operating with half its long-haul fleet out of service because of maintenance and engineering issues, contributing to widespread cancellations that have affected thousands of customers’ international travel plans.

The Qantas-owned budget airline has cancelled eight return services from Sydney and Melbourne to Bali since September 1, plus more from Thailand and Japan, and has been unable to offer some customers new flights home more than a week after their original travel dates.

About 4000 customers had flights to and from Bali cancelled, and about 180 of them were yet to accept alternative flights from the Indonesian holiday island, Jetstar said on Tuesday.

Brisbane woman Nicole De Abel was scheduled to fly with her partner and two young children from Phuket, Thailand, to Sydney on Saturday night but arrived at the airport to discover the flight was cancelled.

Nicole’s mother, Michelle, said the earliest the family could rebook was September 12 – nine days after they were due to fly home.

“They got to the airport, no notification at all that the flight had been cancelled ... no reason as to why the flights had been cancelled,” she said.

“They have been over there for five weeks and they want to come home.”

Jetstar operates 11 Boeing 787 Dreamliners and has confirmed five of them are currently out of service. A sixth jet, which was grounded after hitting a bird, returned to service on Saturday.