Expanding before to export doesn't work any more

In order to provide "full export" to Excel functionality, we expand all data by code before to export to Excel.
It was working until version 2.3, but doesn't work any more with 2.4. Pivot is successfully expanded, but export is truncated.
Launch JSFiddle and click "EXPORT ALL DATA":
https://jsfiddle.net/eyz8evf6/17/
 
'restoreLayoutAfterExport' callback is optional and doesn't affect the issue (it is just used to restore collapsed state).
Minimal code to reproduce the issue:
    flexmonster.expandAllData();
    flexmonster.exportTo('Excel', {filename: 'test.xls'});