When the concessionaire is unable to meet the deadline for the performance of one or more obligations under the contract, or when such timely performance would require resources whose mobilisation would place a manifestly excessive burden on the concessionaire, the deadline is extended by a period equivalent to the period of non-compliance with the performance deadline as a direct result of the exceptional circumstances, at the request of the holder submitted before the expiry of the contractual deadline and before the expiry of the period of exceptional circumstances.