regarding factory calendar change in Solution Manager ITSM

HI,

This is Eunhwa.

I have a few questions regarding adapt factory calendar in Solution Manager ITSM.

There are three things to configure in ITSM factory calendar. For example public holiday, Holiday calendar, Factory calendar.

Mostly, I have heard that In ERP production system, Factory calendar should not be changed manyally.

If then, Solution manager factory calendar should not be changed also? is that change affect to managed systme like erp?

I have heard that solution manater itms factory calendar is used for calculating the service level time. Am I right?

For this reason, my question is that is it okay to maintain factory calendar including public holiday and holiday calendar in Solution Manager ITSM?

Please reply me.

Thanks in advance.