PayrollDate in laborhed for Vantage 8.03.404a, not using Payroll mod

The data dictionary has this to say about the PayrollDate field in Laborhed:

"The Payroll date is the "Logical Day" that labor occurred. In most cases this is the same as the "Physical Day". But when work is done before and after midnight then "Labor Collection" rolls the physical date forward or backward to create a Logical date"

My question is, if you don't have Payroll module, what is the definition of whether the Payroll date is rolled forward or backward? I looked at the laborhed entries, and I have an idea, but I don't want to make an assumption. Is it configured somewhere or just follows a standard rule?

Thank you.

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