Hello, my name is XXXXX XXXXX it is my pleasure to assist you with your question today. No, you can still contest the clause once you reach 65. The contract cannot overrule legislation and the law will always take precedence. In other words, the employer cannot use the contract to go above the law. They can still force you to retire when you reach a certain age but they cannot just do it because of you reaching the age and they need to provide objective justification to ensure they are not acting unlawfully.