Migration is executed automatically by Delta by setting the environment variable MIGRATION_1_7=true.
Additionally, if graph-analytics plugin was enabled, its indices need to be rebuilt. The removal of previous indices and reset of their progress is triggered by setting the environment variable GRAPH_ANALYTICS_CLEANUP=true.
Check the logs to make sure the migration is doing ok and restart Delta after the migration and the tag repair operation are completed without forgetting to remove the environment variables.
The data model for Studios has changed in 1.7.
//TODO Add Studio migration instructions here