Reference https://docs.oracle.com/cloud/farel10/projectcs_gs/OAPEM/OAPEM1461017.htm#OAPEM1313472 Project Labor Demand: How It's Calculated Project executives want to track the labor demand in projects in their organization. The Project Hierarchy Viewer provides project executives a hierarchical view of the enterprise project structure (EPS) along with the labor demand in terms of full-time equivalent (FTE).
Settings That Affect Project Labor Demand
Project application administrators must do the following to set up how project labor demand is calculated:
Organize projects into hierarchical groups on the Manage Enterprise Project Structure page.
Change the quarterly FTE hours for the organization on the Define Project Management Implementation Options page, if different from 520 hours.
Note: You can choose to view labor demand annually instead of quarterly. The Project Hierarchy Viewer uses the current date to determine which year or quarter to display.
How Project Labor Demand Is Calculated
The Project Hierarchy Viewer calculates project labor demand in the following manner:
Spreads the allocation hours from the Manage Project Resources page evenly over the days that the resources are allocated to the project.
Divides the quarterly project allocation hours by the quarterly FTE hours to get the labor demand.
Rolls up the quarterly and annual labor demand up the hierarchy.

Shift is one of the key elements in defining project and resource calendars. Two additional key elements that are required to define the project and resource calendars are:
Schedule Exceptions: These are dates or periods that override the regular workday patterns and shifts of a calendar. They can be used to define holidays, vacations, or other special events that affect the availability of resources or projects.
Workday Patterns: These are patterns of working and nonworking days that repeat over a period of time. They can be used to define the standard working days and hours for a calendar. Time off, expenditure type, and accounting calendar are not key elements in defining project and resource calendars. Time off is an attribute of a resource assignment that reduces the availability of a resource. Expenditure type is a classification of costs that determines how they are processed and accounted. Accounting calendar is a calendar that defines the accounting periods and dates for transactions. Reference: https://docs.oracle.com/en/cloud/saas/project-portfolio-management/20c/oapfm/manage-project-resources.html#OAPFM2356131

Project gate statuses are values that indicate the progress or completion of a project gate. A project gate is a checkpoint that marks the end of a phase or stage in a project lifecycle. Three of the project gate statuses are:
Open: This status indicates that the project gate is not yet ready for review or approval.
In Review: This status indicates that the project gate is under review or approval by the gate reviewers or approvers.
Closed: This status indicates that the project gate has been reviewed or approved and the project can move to the next phase or stage. Approve and Draft are not project gate statuses, but actions that can be performed on a project gate. Approve is an action that allows a gate approver to approve a project gate and change its status to Closed. Draft is an action that allows a gate owner to create or edit a project gate and change its status to Open. Reference: https://docs.oracle.com/en/cloud/saas/project-portfolio-management/20c/oapfm/manage-project-execution.html#OAPFM2356251

When a project invoice is transferred or created in Receivables, the project sends only the invoice header and invoice line description to Receivables, not the invoice distributions. The invoice distributions contain the detailed information such as quantity, unit price, and line total. Therefore, the Receivables invoice does not show these details, but only shows a quantity of 1 and a unit price equal to the line total. Reference: https://docs.oracle.com/en/cloud/saas/project-portfolio-management/20c/oapfm/manage-project-invoices.html#OAPFM2355931

Ref: https://docs.oracle.com/en/cloud/saas/project-portfolio-management/18c/oapfm/project-costing-configuration-define-project-costing-integrations.html#OAPFM174886 How can I validate distribution sets for projects information?
Oracle Fusion Projects performs validations on Oracle Fusion Payables distribution sets for payables invoices at the time you create the actual distribution set lines. It validates the project and task number during the invoice validation.
Distribution sets are typically used on recurring transactions, and the associated project does not have transaction controls. When you create a distribution set in Oracle Fusion Payables, the distribution set line is not validated against the project transaction controls in Oracle Fusion Projects because you do not enter an expenditure item date, which is required for transaction control validation. The expenditure item date is not provided because you use the distribution sets for an indefinite period of time.