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The formula works correctly for everything with a number. I think this is an easy formula, I just can't figure out where the override button is
The Formula Wizard helps you create formulas by providing a list of relevant field variables, available formulas, and syntax help. Click Formula Help to open the wizard or, if you see a choice between Standard Text and A Formula, select A Formula and then click Formula Help
Adding months to a given date is a very common use case. But accomplishing this with a formula field of a field update formula used to be a tricky task