The flight attendants' group says it should have an answer by early next week.
For the pilots, the unionizing efforts continue at the airline, but the job is now more difficult.
Two employee groups, the WestJet Professional Pilots Association (WPPA) and the WestJet Professional Flight Attendants Association (WPFAA) have been working since 2013 to organize their fellow employees into formal unions.
Both groups were working against a deadline of June 16 for something called automatic certification, in which a union can certify if 50 per cent plus one employees sign a union card. As of the 16th, federally regulated employees, such as those who work in the airlines, also need to hold a secret ballot.
The WPFAA says auto certification is still a possibility for the flight attendants.
A representative of the union would not say if the WPFAA had filed its union cards to the CIRB for certification, but said that the group is waiting on clarity from the board.
The group says it expects to have that clarity early next week.
WestJet pilots will now need secret ballot vote
With the secret ballot rule now in place, the pilots' group will have to notify the company once it is ready to hold a vote.
"It becomes an extra hurdle for the union to overcome before it gets certified," said Jim Stanford, economist with Unifor.
The WPPA wouldn't comment publicly, but did send an update to its pilot members saying a secret ballot would now be needed. The group said it would continue its efforts and decide on a date for that vote.
Each employee group has different reasons for organizing.
The pilots are looking for more transparency on upgrading from first officer to captain, as well as more equality with their colleagues who fly for WestJet's regional airline, Encore.
Among other things, the flight attendants' group is seeking more input into their work rules.
Both groups are looking for a more formal relationship with management in an airline that has grown rapidly over the past several years, launching Encore, expanding its crew bases to Vancouver and Toronto and adding wide-bodied jets to fly to Europe.
WestJet management responded to the union drive last week by asking employees to think hard before signing a card.
Clive Beddoe, the co-founder and current chairman of the airline, also wrote to employees, saying WestJet's success hinged on its "unity of purpose" and co-operation instead on confrontation. Beddoe said he strongly disagreed that more formal representation was needed.
WestJet said in a statement this week that, at this point, it is continuing to work with its people through its proactive communications team.
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