The position depends on whether the modification is governed by the pre-Procurement Act 2023 (PA 2023) regime (Public Contracts Regulations 2015 (PCR 2015), SI 2015/102, Utilities Contracts Regulations 2016 (UCR 2016), SI 2016/274 or Concession Contracts Regulations 2016 (CCR 2016), SI 2016/273), or instead by the PA 2023. The modification will be governed by the pre-PA 2023 regime if the contract itself was awarded before Monday 24 February 2025, or if the procurement for the contract in question started before that date, even if the contract itself has not been awarded by that date. It will be governed by PA 2023 if the procurement for the contact starts on or after Monday 24 February 2025. The position under the pre-Procurement Act regime Under the pre-PA 2023 regime, express provisions on contract modifications are to be found in PCR 2015, SI 2015/102, reg 72, UCR 2016, SI 2016/274, reg 88 and CCR 2016,