Hi @SmartAcre,
HubSpot expanded on the functionalities of calculation properties: Create calculation and rollup properties
What you’re trying to do,can now be easily achieved with such a property, see this example that calculates a date 30 days after the record create date:
The number of days is the first number in brackets. The rest of the numbers are there to calculate the amount of milliseconds as that’s the unit HubSpot uses here.
If you want to calculate a date before, simply switch the + for a - sign.
Best regards!