Downgrading from AWS Aurora MySQL 5.7 to AWS Aurora MySQL 5.6
I think exporting to a SQL file first would work:


export to a SQL file (in S3 or elsewhere)
import to a 5.6 instance


See this: Amazon Aurora Can Export Data into Amazon S3, where it says:


  You can now use the SELECT INTO OUTFILE S3 SQL statement to query data from an Amazon Aurora database cluster and save it directly into text files in an Amazon S3 bucket. This means you no longer need the two-step process of bringing the data to the SQL client and then copying it from the client to Amazon S3. It’s an easy way to export data selectively to Amazon Redshift or any other application.
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