QB Issue Resolution:

In QB Desktop there is a option switch available in some type of reports that control this display:

Run the report to screen then: Customize button > Display tab > Advanced button > Open Balance : REPORT DATE

Resolution for Issue 'How can I look back and find unpaid invoices at date in the past. I need to know who owed us money at the end of August.' available: Yes (Solved).
Source: Intuit Community forum.

How can I look back and find unpaid invoices at date in the past. I need to know who owed us money at the end of August.: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for Balance
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Error Recovery for Balance [Canada]
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