Can we create a custom warning message for Correct/Update assignment

Summary:

Is it possible to add a custom warning message to be triggered for Correct/Update assignment for certain scenario's?

Content (required):

Hi, we would like to be able to create a warning message for certain scenario's when there is a Update/Correction to the Assignment.

eg if the assignment has assignment level costing, then any change to the assignment should give a warning to check the costing is still valid.

We have been able to do this in the Absence module using a validation Formula?

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