Limit users per each BU when creating vacation rules

Summary:

When creating vacation rules, the system shall limit the number of users that can be associated with a single Business Unit

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Hi all, we are trying to limit users as per each business unit when creating vacation rules. However, creating a custom role & assigning a security profile does not work. This works only on underlying UI like requisition but not on BPM which are core oracle pages. Is there any workaround how we can achieve this?

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