Can I sort my customer list into two lists based on "before" and "after" dates?

Hi there, @Omichael.

As of the moment, there isn't an option to sort the customer list based on the "before" and "after" date. In the meantime, you can export the customer list (Customer Contact List) report to excel. This way, you can sort the list and customize the customer information the way you want it. 

Here's how: 

1. From the left menu, select Reports.
2. Select Customer Contact List.
3. Click the small Gear icon, and mark the Create Date and Last Modified checkboxes. 
4. Select the Export icon next to the Print icon, then choose Export to Excel.

Keep an eye out for new product features and updates here at the QuickBooks Blog. Also, from there, you can check the new features and improvements released this month, like sales tax filing, new credit card payments workflow, and create custom roles.  

I wish you and your business continued success. Please let me know if you have any other questions.