Cut over period mean end user will not be having access to production SAP so that there will be no changes in transactional data,
The final phase before going live with SAP is often referred to as the cutover phase, which is the process of transitioning from one system to a new one. The organization needs to plan, prepare and execute the cutover, by creating a cutover plan that describes all cutover tasks that have to be performed before the actual go-live. Examples of cutover tasks are:
Review and update all systems-related operations procedures like backup policies and system monitoring
Assign ownership of SAP’s functional processes to individuals
Lock down the system, i.e. do not make any more changes to the SAP system