Upgrading from OJS2 to, convertQueries dies without an error

I am upgrading a large OJS2 installation to and the upgrade dies every time during convertQueries script.

All errors should be visible and even warnings and notice level errors are showing during the upgrade. However, convertQueries just dies without giving an error.

Any suggestions?

follow-up here that after fixing another issue (Upgrade to 3.1.1-2 from 2.4.8 PHP Fatal error: Call to a member function getStatus() - #84 by ajnyga) and then running the upgrade script in two parts (added a die() just before the convertQueries, made a backup of the db at that point and then continued the upgrade from that point) the convertQueries function finished without problems…