Siebel Integration with ORS

 We are planning on using the OOTB Siebel/ORS integration as well as Asset-based Order Management and have come across the following challenge:

Upon submitting an Order we will generate Activity Plans where typically one of the Activities generated will be a Field Service Activity, to be assigned to an engineer. The scheduling will be done using the ORS integration. After an Order is revised/modified the submit will generate a new Activity Plan and we will cancel/clean up the existing ones.

The challenge is the case when the engineer makes changes to the order on site, we would then want to be able to tell ORS to keep the existing slot/stop on the current engineer but this will be represented by a new Activity (and we would want to cancel the existing one). The duration of the Activity may be longer as well which may cause the engineer to be ineligible for the assignment (due to the next scheduled assignment) but we would want to be able to override this (to ensure the same engineer remains on site and finishes the