Aged Payables not showing 1-30 days


I do not know if i found a bug or am i doing something wrong. When i run a report on aged payables it will show the previous month and the current month under current and if i move the month forward the month which should have been under 30 days moves over to 60 days (which is correct) the issue is that it did not show at first under 30 days. Here is how to reproduce.

  1. Supplier Invoice due date set to the end of the following month. So invoice date is 1/6/2018. Due date 31/7/18
  2. Run report aged payables set report date to 31/7/18, it will show June invoices and July invoices under current, move report date to 30/8/18 and June invoices will not be under 60 days and July will be still be under current.