In Italy:
- non-FIFA referees are allowed to officiate in Serie A only for ten years, then they have to retire
- FIFA referees are allowed to stay until they are 45yo
- only the biggest names like Rizzoli or Rocchi are allowed to get a one-year derogation (that's why Rocchi had to step down being 46yo).
So it depends on national association rules if a certain referee could continue on FIFA niveau or not.