Expense Accruals set to blank

Summary:

We are currently having Expense Accruals set to Period End. This has been running for a few months.

We are also using Projects, but the PO process is not in place and therefore Period End is used.

Customer is strugling with data and don't want any period end posting in GL.

Can we just set this setting to nothing (blank)?

How will a blank setting affect current PO's?

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