Since the 1.30 upgrade (not sure if it's actually related) for every few wikis I get the error below. When I remove the wikis from CW_WIKIS the script continues for a few seconds, until it reaches another wiki and I encounter the error again.
[77afe223f47291496b9b2069] [no req] MWException from line 1673 of /srv/mediawiki/w/includes/page/WikiPage.php: Could not find text for current revision 4. Backtrace: #0 /srv/mediawiki/w/includes/page/WikiPage.php(1625): WikiPage->doModify(WikitextContent, integer, User, string, array) #1 /srv/mediawiki/w/extensions/MirahezeMagic/maintenance/manageInactiveWikis.php(183): WikiPage->doEditContent(WikitextContent, string, integer, boolean, User) #2 /srv/mediawiki/w/extensions/MirahezeMagic/maintenance/manageInactiveWikis.php(122): FindInactiveWikis->warnWiki(string) #3 /srv/mediawiki/w/extensions/MirahezeMagic/maintenance/manageInactiveWikis.php(76): FindInactiveWikis->checkLastActivity(string) #4 /srv/mediawiki/w/maintenance/doMaintenance.php(92): FindInactiveWikis->execute() #5 /srv/mediawiki/w/extensions/MirahezeMagic/maintenance/manageInactiveWikis.php(212): require_once(string) #6 {main}