The GP Conditional Logic Dates perk allows you to show/hide fields based on the selected date in a Date field. Only Datepicker Date fields are currently supported.
How does it work?
This perk allows Date fields to be selected when creating conditional logic rules for your fields (and other places conditional logic is supported). It integrates seamlessly with Gravity Forms’ existing conditional logic UI.
After selecting a Date field, you will select the operator for comparison (i.e. less than, greater than, is or is not) and enter the date value to which the Date field should be compared.
Usage Specifics

Date value must be entered manually using the US date format: MM/DD/YYYY.
Will add support for jQuery Datepicker for selecting the date value in a future version.
Supported operators: “is”, “is not”, “greater than”, “less than”.
Special conditional-logic-only merge tag supported: {today} Allows conditional logic to be applied to fields based on whether the selected date is, is not, is greater than or is less than the current date.
{today} merge tag supports modifiers for making date comparisons like:

Date is at least 2 weeks away: {today:+2 weeks}
Date is no more than 90 days before today: {today:-90 days}

Date Wildcards: If you want to target a specific day of the month, a specific month, or a specific year, you can use the * character as a wildcard.