The Session Registrants Report will have this.
Run the report then click the gear/ data icon at the top right. Select "Change Report Data". That allows you to add/ remove data columns. Add the "Session Registration Date" field. It's near the bottom of the list of potential fields, under the 'Session Registration Information' heading. It is a date/time field, so you will know the exact time someone registered for your session.
You can also click the gear/ data icon and select "filter Report Data" and then filter to just include the one session you care about.
Good luck!
-Tom
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Tom Neuburger
Associate Director, Crm Center Of Excellence
Smith College
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