Yes, you can. If you enabled developer mode just use these simple solutions in the step settings advanced section Dynamic settings field. 

There are available 4 options:

   "function(date){return (date.getDay() === 5 || date.getDay() === 6)}",

If you’d like to make certain dates unavailable for selection, there are multiple methods of doing so.

  1. Disabling specific date
  2. Disabling a date range
  3. Disabling dates using a function

more info

   "function(date){return (date.getDay() === 1 || date.getDay() === 2)}",

This is the enable option, which takes in an array of date strings, date ranges and functions. Essentially the same as the disable option above, but reversed.

more info

The minimum date that a user can start picking from (inclusive).

Overrides the value from the Start date field

The maximum date that a user can pick to (inclusive).

Overrides the value from the End date field