There's nothing in the OJS codebase that would cause a change in a PHP file not to be reflected immediately, and as long as file dates are correct, any PHP caches installed on the server (e.g. Zend Accelerator) should notice that a new file has arrived and recompile it. I'd suggest double-checking that you're changing the right file -- it's easy to get confused, for example, when modifying classes/submission/sectionEditor/SectionEditorSubmissionDAO.inc.php vs. classes/submission/editor/EditorSubmissionDAO.inc.php. If you have a specific question about the code, feel free to ask.
Open Journal Systems Team
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