This process is relevant for migration up until and including 2.6.13. From version 2.6.14, the following process should be used https://yarnlab.atlassian.net/wiki/x/B4Bvy

Overview

When performing a phased migration, it is recommended that a number of object types are changed to NOT be site specific. This will minimise minimize any issues encountered during a phased migration prepare step due to dependency issues,

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