More than a month of tacking several issues which have come up as a result of the carrier's switchover to a whole new reservation system will, it seems, definitely affect WestJet's fourth quarter earnings, a fear which has been shared by airline as well.

Canada's second largest carrier has shared that, amidst fears of a weak fourth quarter, it has postponed the launch of its various new offerings including the frequent-guest and credit-card program, until next year. Right now, the airline wants to stay more focused on combating the several service disruption issues that have reared their head as a result of its new SabreSonic reservations system.

"Regrettably, the transition has affected the level of service that our guests have come to expect and deserve, and these service issues are carrying on longer than we originally anticipated", said WestJet's President and Chief Executive Sean Durfy.

While asserting that the loss that has been incurred because of the switchover cannot be quantified as of now, WestJet did say that it was estimating that the fall in revenue could be around 11-13% as compared to last year.

On Thursday, as confirmed by the Toronto Stock Exchange's figures, WestJet shares slipped by 29 cents to close at $11.65.