The bargaining agents have a file, a constitutional challenge to the current legislation, and it has been put in abeyance with the understanding that the current government would repeal it, but certainly if the legislation is not repealed, the bargaining agent, I would suspect, would restart the charter challenge, and their main argument is that the current legislation is very similar to the legislation that was enacted in Saskatchewan and declared unconstitutional.
On April 30th, 2018. See this statement in context.