Can we take effective date as past date to schedule update or calculate schedule process ?

Summary:

Hi Experts,

I have to schedule one absence plan here I asked them to take current date as effective date but they asked me to take past date as effective date.

here what is the effective can I take.

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I have to schedule one absence plan here I asked them to take current date as effective date but they asked me to take past date as effective date.

here what is the effective can I take.

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