Error on delta migration step 8

Hello
Running delta migration step 8 and get the below error.
Please advice

Processing in step #8.................................................................PHP Error[2]: Creating default object from empty value
    in file /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/protected/controllers/Step8Controller.php at line 770
#0 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/protected/controllers/Step8Controller.php(183): Step8Controller->_migrateReview()
#1 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/protected/commands/RunCommand.php(58): Step8Controller->actionRun()
#2 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/protected/commands/RunCommand.php(28): RunCommand->_migrateData()
#3 unknown(0): RunCommand->actionIndex()
#4 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/yii/console/CConsoleCommand.php(172): ReflectionMethod->invokeArgs()
#5 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/yii/console/CConsoleCommandRunner.php(71): RunCommand->run()
#6 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/yii/console/CConsoleApplication.php(92): CConsoleCommandRunner->run()
#7 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/yii/base/CApplication.php(184): CConsoleApplication->processRequest()
#8 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/yii/yiic.php(33): CConsoleApplication->run()
#9 /home/cloudpanel/htdocs/test.ovationmusic.com/pub/ub-tool/protected/ubdatamigration_cli.php(5): require_once()
#10 /home/cloudpanel/htdocs/test.ovationmusic.com/bin/ubdatamigration(4): require_once()