4.5.—(1) Where a party has failed to comply with a rule, practice direction or court order, any sanction for failure to comply imposed by the rule, practice direction or court order has effect unless the party in default applies for and obtains relief from the sanction. (Rule 4.6 sets out the circumstances which the court may consider on an application to grant relief from a sanction.)
(2) Where the sanction is the payment of costs, the party in default may only obtain relief by appealing against the order for costs.
(3) Where a rule, practice direction or court order—
(a)requires a party to do something within a specified time; and
(b)specifies the consequence of failure to comply,
the time for doing the act in question may not be extended by agreement between the parties.