Hawaiian Airlines flight attendants held another major labor demonstration today at Daniel K. Inouye International Airport in advance of taking their first strike vote in the history of the 90-year-old company.

The contract between Hawaiian Airlines management and the flight attendants, who belong to the Association of Flight Attendants-CWA union, became amendable on Dec. 31, 2016. The company and its flight attendants union have been in mediation since the fourth quarter of last year. So far, four protests including the one today have been held in Honolulu and a fifth protest was held in Los Angeles International Airport.

While the atmosphere is contentious, it’s hard to predict if Hawaiian flight attendants actually will go on strike, even if a majority approve the vote, which is slated to begin Oct. 28 and run through Nov. 20. Some 2,100 flight attendants are eligible to vote.

>> Click here to see more photos of the demonstration.

Often such votes are mostly symbolic since airline workers fall under the Railway Labor Act, federal legislation which discourages transportation industry workers from going on strikes and lookouts that could create trickle-down economic dampening. The RLA requires transportation unions to get approval from a federal mediator to go on strike. Even if they get permission, they can’t strike until a 30-day cooling off period passes. If they do go on strike, President Donald Trump has the power to order them to go back to work.

“We’ve never had to take a strike vote before. It’s a serious step and we want to send a serious message to management,” said Sharon Soper, a flight attendant who has worked at Hawaiian Airlines for 54 years.

Hawaiian Airlines spokesman Alex Da Silva said progress has been made and the airline is focused on working with AFA negotiators through federal mediation to finalize a new contract. The latest union announcement will not affect flight operations or guests’ travel plans since self-help actions are illegal as long as good faith negotiations are ongoing, Da Silva said.

“Hawaiian and AFA have reached tentative agreements on many issues since negotiations began and we are working hard to finalize a deal on remaining issues through ongoing mediation,” he said. “We remain entirely focused on mediating the final items of a contract that recognizes our flight attendants’ contribution to our success in a way that is equitable with other bargaining units and reflective of our competitive standing in the industry. “

But the union said there are still sticking points pertaining mostly to wages and benefits. Another union concern has been that Hawaiian’s retirement plans do not provide enough continuity of medical benefits.