Don't forget about the Saved Packages list. Before installing the OS update, update your saved packages list then run EPR to remove all patches. Once all patches have been updated for 3.0.4, just open your Saved Packages list & select Install all. No need to remember or write down the patches, preware does it for you.

If you want to make sure you'll have the files, you can always run Save / Restore, select preware, then save & copy the saverestore directory somewhere safe, install OS update, copy saverestore directory back to device, restore preware with Save / Restore, Install All from Saved Packages list in preware.