A NSW government agency had a requirement to move a number of their Critical applications infrastructure from GovDC (on Premise) to the cloud (AWS) to mitigate infrastructure end of life risks.    A Migration testing strategy was required to be delivered and signed off by key stakeholder along with a number of test plans to be developed per platform. There were 4 key platforms to be migrated ranging from all non–production instances to production instance.  There were approximately 50 environment instances in non-production to be migrated.  Non productions environments included development, system test, System Integration, UAT, and pre-production. A Test plan per platform was required along with discovery sessions with different stakeholders from development, testing, operations and business stakeholders. A suite of test cases were developed per platform and automation of approximately 50% of suite was created to reduce execution time.  The testing was carried on both non-production workloads on premise and to–be Cloud environments along with conducting comparative test cycles to detect any anomalies.  The testing was carried out on both batch and High priority operational scenarios. The Client’s main application environments had several internal shared components such as a document/image repository, batch components (Batch server and secured file–share landing zone) & CA Autosys which added more complexity along with external agencies feeds, 3rd party services and payment gateways.