Procedure for getting mysql.flush_rewrite_rules removed

In this specific scenario, I would recommend to open a support case under Basic support plan itself under "Account & Billing" inquiries, further it can be analyzed on use case basis if this can be further troubleshooted by the technical team.

Hope it helps and if it does, I would appreciate if answer can be accepted so that community can benefit for clarity when searching for similar enquirers in Repost, thank you ;)

Here are a few things you can try to resolve the preupgrade check failure:

• Review the upgradeFailure.log file closely to understand the specific error messages. This will help identify the root cause.
• Check if the error is related to any database objects like stored procedures that may be incompatible with MySQL 8.0. You may need to drop or modify such objects before upgrading.
• Take a backup of the database, restore to a test instance and run preupgrade checks there to isolate issues. Drop/recreate incompatible objects and test upgrade.
• Open an AWS Support case. For RDS instances, support engineers may be able to further investigate internal issues and help resolve the failure.
• As a last resort, try performing a DB snapshot and creating a new instance from the snapshot to get a clean state. Then attempt the upgrade.