The £500 is less than RPI, and not consolidated, so it is a real terms cut.
....
It's become a perfect storm for a vote for industrial action.
RPI is currently 0.9% so every Network Rail employee who was balloted is on at least £55,556 by your claim. No wonder people want industrial action if the semi-skilled employees get £55,556, the skilled ones will want salaries comparable with the Prime Minister.