During the update execution, you are informed about P-messages on the SUM user interface by means of a Checks.log flag (see also SUM UI: Flags). The flag is displayed as warning with a corresponding message. At that moment, you can already process this type of error.

You can also tackle P-errors at a later point in time in the Postprocessing roadmap step. In any case you must ensure that all remaining P-errors are solved before you start the productive system.

If any of them still exist, process them as follow-up activity after the update procedure is completed.