QB Issue Resolution:
Yep – unreconcile was added in the 2013 version (and is in 2014, obviously, too). But only for reconciliations performed in that version.
Resolution for Issue 'how do I undo a prior reconciliation on an account?' available: Yes (Solved).
Source: Intuit Community forum.
how do I undo a prior reconciliation on an account?: 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 Quickbooks
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