I'm wanting to create a job variable based on some calculations of the current date.

Basically job var = x and (y or z).

I can't see any functions for 'and' or 'or' — are they available? If not I can probably fake it with some maths.

If you can't build what you need with the logic functions you may be at the point where you need to use .net or powershell scripts.

You have some control by using the Flow (see video tutorial). But if there are more complex things I recommend Powershell or .NET. With the latest version you have the Task repository. With that you can create .NET Code or Powershell and then evaluate that code through a VisualCron Variable and return a result.

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