It doesn't really resemble a defined benefit plan at all, in that the benefit is only.... If for any reason—not only the solvency of the employer, but merely if the management of the fund were unable to pay out what would otherwise be a defined benefit—the benefit shall not be defined, it will shrink, because the employer is not compelled to make up a deficiency.
On June 1st, 2021. See this statement in context.