We have added few WP_CLI command in AnsPress 4.0.6. Previously many people have reported that they were unable to upgrade from AnsPress 3.x to AnsPress 4.x. This Issue was happening with site having over 1k questions. To resolve this issue we decided to add WP_CLI command. Give it a try by running:
wp anspress upgrade
We have tried this command on site having more then 40K questions. Command completed in approx 11 minutes without any issue. Even though its safe to use this command in live site but we will recommend a full backup.