I needed to save the pre-post report, but instead I accidentally ran the post process which marked my transactions as posted. In addition, on the history, I deleted this history thinking this would undo the post process. Is there a way to undo?
There is no way to undo a post process in Altru. When running the post process try unmarking the option to "Mark revenue records 'Posted' when process completes". This will allow you to run the process multiple times as a preview before you actually flag those records as posted.
Steps to Duplicate
Go to Financials > post revenue to GL.
Click on the affected process.
Go to the History tab and see there is no history for the process ran on July 6th for dates up to July 4th.
Click Start Process and change the post dates up to July 4th.