I was going to say what Jean-Guy said. To know that answer, you would have to have the actuary look at it. The PBO would have to look at the question, or you would have to have someone look at exactly what the cost would be.
There doesn't necessarily have to be increased contributions. It could be a solution, like the.... In the mandate letters, for example.... The veterans fund that was suggested doesn't get to the root issue but, at the very least, there are funds there.
There are other solutions other than increased contributions, but increased contributions could possibly be one. This is one of the reasons why a study would be helpful from an actuarial perspective.