If there are 15 activities within the Priced Activity Schedule for 15 months prelims and you manage to beat the program by 2 months can the contractor apply a compensation event to withhold payment of the last two months prelims/activities that were not carried out?
You need to submit a revised activity schedule as it no longer reflects how you plan to do the works. These two months worth of costs should be allocated across other activities so that the total of the Prices is still the same but then you can get paid the amount you originally allocated. This is a lump sum fixed price contract and any such benefit should be yours not the Employers. they would be very quick to point out that if you need to stay on site an extra two months you can not automatically claim for those two months (unless it is down to a compensation event).
Completely agree with Glenn on this one, this question demonstrates the problem caused by prelims being defined as separate activities and why I always advise they should be included in each activity like risk, overheads and profit.