Moving site from WordPress to Drupal
For some reason, the back up hadn't recorded the updated version of CiviCRM (it may have happened before I reran the update script) so when I checked the domain table in the back-up just now, it was still showing version 4.7.29. I did a manual back-up AFTER double-checking the domain/version was correct in the WordPress site, then I copied over the database tables again and it's working.