@jkabot thanks for the suggestion but no joy with fireSlavingSync: true I have a loop that is trying to add n items to the transaction. Before each call to setCurrentSublistValue I’m doing a console.log(’adding item <stuff>’); I can see those coming through one after another, but nothing on the UI changes until the end of the loop or SuiteScript error happens. So it’s like the UI doesn’t update until the script halts.