Within how many days must a newly created charge (such as a mortgage over company property) be registered at Companies House to ensure it is valid against a liquidator or administrator?

Under Section 859A of the Companies Act 2006, a charge created by a company must be registered at Companies House within 21 days beginning with the day after the day on which the charge is created. Failure to do so makes the charge void against a liquidator, administrator, or creditor.