If the Employer takes over works prior to Completion, then this will be a compensation event under 60.1(15). Any additional cost the Contractor incurs would then be recoverable, and also there would be an entitlement to move Completion Date if planned Completion is affected, which would then mean they are not liable for delay damages.
The only way that a Contractor would ever get paid back delay damages is if subsequently that there was an agreement that Completion Date should have moved and that either less delay damages should have been paid or none at all. In this instance the Contractor would also be entitled to interest on the money they had already paid. The compensation event process is the only way that Completion Date can be moved later so it would have to be an un-agreed compensation event where this eventuality could occur.
The only way that a Contractor would ever get paid back delay damages is if subsequently that there was an agreement that Completion Date should have moved and that either less delay damages should have been paid or none at all. In this instance the Contractor would also be entitled to interest on the money they had already paid. The compensation event process is the only way that Completion Date can be moved later so it would have to be an un-agreed compensation event where this eventuality could occur.