Do unions have to renegotiate long term contracts in order to change health insurance plans?

could this be the reason they get the delay in having benefits taxed?
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Yes. According to my friends that work for the American auto companies and belong to the UAW, their health care is in the contract. There is no dipping into that contract to change a little something here or there until it's time for negotiations. Negotiations only happen when the contract is coming to an end. Depending on what contract new hires come into when they first start, (the contract is already in place, new hires have no say so) that's the bennies they get. It's actually illegal to open contract negotiations without a vote and everyone agreeing to it, in other words, management cannot change the contract on their whim.
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