With Change Management, management decides to act to improve the organisation.
With a Turnaround intervention the organisation probably has no other option but to act immediately, and with a Rescue situation, decline and distress has set in and its too late for current role players to change the course of the entity.
Change management is the fundamental rethink of all processes within the organisation. Especially when organisations are in decline or having operational and profitability difficulties, normally as management does not have processes and procedures in place to benefit from trading operations.
The difference between these three interventions, is only in their timing.