If you are just making changes to constant fields then you shouldn't have to recompile your RPG program for your changes to take effect. If you are adding/removing fields or formats, then you will need to recompile your RPG program to make the changes effective.
It's possible that you are not using your newly compiled print file. Some reasons for this could be: The production print file is higher in your library list than your print file or there is an override in your RPG program or a previously called CL program that causes it to point to a print file in a library that is not the one you just created. Try to watch the job as it's running and see if it's using your new print file. If it is, then you'll need to recompile your RPG program.
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