|To find the original Chatter post and the date you'll need to create a custom report and use the Feed Revision report type. For more information about building custom reports, read our custom report types documentation.
Feed Revision report to check for original Chatter post
1. Create a Feed Revision report type if it's not created yet. Below are the steps:
a. Click Setup.
b. Under "Build," click Create | Report Types.
c. Click New Custom Report Type.
d. Click Feed Revisions as Primary Object.
e. Enter the Report Type Label, Report Type Name, Description fields.
f. Click the category to store the custom report type in.
g. Pick a Deployment Status.
h. Click Next.
i. Click Save.
2. Create a Report and make sure that you use the Feed Revision report type.
3. Drag and Drop the fields from the Fields Pane to the Preview Pane. Raw Value column shows the original value of the post while Created Date column shows the original date of the Post.
For more information about creating a Report, click Build a New Report.
NOTE: Only the original Date, without information about time of the post, is available. If you want to check the original time of the post, use Data Loader.