NEC3 Short Form omission of work partially commenced

We are main contractor, we have a scheme to deliver and some elements of the scheme are contractor design. In order for the client to save money,they are omitting works,which in Short Form contracts is a change to the quantities in the pricing schedule. However, say for example, we have carried out some design work for s contractor design element,and before our design id approved the client and PM decide to omit that particular works package, am I entitled to then argue this should be a CE and as such dealt with by defined cost + fee %. The QS seems to believe that contractually he thinks as no physical works had commenced he can simply zero the item,with us left with nowhere to recover design costs.