Acceleration under the contract is under clause 36 and is only for when the Contractor is instructing a quotation to bring forward the Completion Date. The Subcontractor gives a quotation, and the Contractor either accepts it and pays the money but Delay Damages will now be from the revised Completion Date, or rejects the acceleration quote and nothing changes. They cant make their own assessment of the quote.
However, what you have here does not sound like acceleration under the contract. It is more a case of speeding up to mitigate a delay or to maintain the original date, rather than bring an original date forward. The Contractor can instruct this, but they need to be careful as this would sound like a change to the Works Information and therefore a compensation event. Any increase (or decrease!) in costs be working weekends or additional hours will be assessed as a CE - but remembering to take into account the savings as well i.e. saved prelims at end if working weekends means Subcontractor finishes earlier. Contractor therefore has to be very careful when they instruct such things, but they can if the wider picture is more important to them.
Otherwise it should simply be the case that the Subcontractor is motivated to maintain there original date either with incentives, or the fact that delay damages will mean they do not want to be late. Contractor cant put new constraints upon a Subcontractor that they hadn't priced for and expect it to have no impact.
However, what you have here does not sound like acceleration under the contract. It is more a case of speeding up to mitigate a delay or to maintain the original date, rather than bring an original date forward. The Contractor can instruct this, but they need to be careful as this would sound like a change to the Works Information and therefore a compensation event. Any increase (or decrease!) in costs be working weekends or additional hours will be assessed as a CE - but remembering to take into account the savings as well i.e. saved prelims at end if working weekends means Subcontractor finishes earlier. Contractor therefore has to be very careful when they instruct such things, but they can if the wider picture is more important to them.
Otherwise it should simply be the case that the Subcontractor is motivated to maintain there original date either with incentives, or the fact that delay damages will mean they do not want to be late. Contractor cant put new constraints upon a Subcontractor that they hadn't priced for and expect it to have no impact.