If the programme isn’t accepted does the S/C get on with works based on previously accepted programme or the latest proposed programme?
The requirement to “get on with it” exists whether you have an Accepted Programme or not! Clause 30.1 requires the Subcontractor to do work “so that Completion is on or before the Subcontract Completion Date.” Failure to comply with this will usually result in the Contractor deducting delay damages (assuming Option X7 applies). Note there is no obligation to do the work in accordance with the Accepted Programme. How the work is organised may need to change as things progress, especially to mitigate the effects of any delays that have been experienced.
In summary, the Subcontractor should do whatever it can to meet the Subcontract Completion Date if the programme needs to change then so be it, regardless as to whether the Contractor accepts the revised programme or not. Sticking to a previous programme may put the Subcontractor at risk of being late and damages being deducted.