Then it's a bit early to go on altitude camp in December already. She took a break from racing to improve her form, but it hasn't. If anything it's gotten worse.It depends what Vos is aiming for. Theoretically she should have gone well on that track, but perhaps her aims of the altitude camp are beyond cyclocross.
I think as far as the national championships go that rule doesn't apply, after all Backstedt is British elite champion but she still races as an U23.This rule that someone who steps up to Elites can't be eligible to the U23 World Cup classification is a bit moronic, when they all race together.
Now Shirin wins the World Cup because her other U23 rivals decided to step up to Elites during the season to focus on another goals (EC for Fem and NC for Puck). Now Shirin can do the same in the week between Besançon and Worlds (unlike Puck, she could wait because she didn't want to take part in NC) and keep her U23 World Cup.