What happens if you are writing checks near the end of the month, but you since don't plan on mailing them until the 1st, you want them to be dated on the 1st?
Go to Accounting > Make Payments.
By default, the Payment Date is today's date, and the Post Month is the current month, but you can change them as needed.
In this example, we've changed 10/30/2018 to 11/01/2018 and 10/2018 (the post month) to 11/2018.
When we click Make Payments, the checks will show 11/01/2018.