It's unlikely to affect the rate of damages per day / week but it might affect the duration that you are apply the rate to. This will depend on exactly how the duration is stated in the contract. For example if 40 weeks is stated, you have to know when the 40 weeks started to calculate when the liability to pay damages starts. So the 40 weeks needs tying to another date or an event e.g. 40 weeks from starting on site or 40 weeks from possession or 40 weeks from contract award etc.