Hi,
In ArcGIS Pro 2.6 it seems that you can format date data that is inserted as dynamic text using the information in this page: Format date and time dynamic text—ArcGIS Pro | Documentation however this only seems to apply to dynamic text inserted using options like the Current time or Date exported.

I have a date field in my index layer that I only want to display as dd/mm/yy, but if I apply the format option it does nothing.
e.g.
Date Exported: <dyn type="layout" name="Base Component Layout" property="dateExported" format="short|short"/>
vs
<dyn type="page" property="attribute" field="rev_date"/>
It isn't mentioned in this article at all: Using dynamic text with Data Driven Pages—Help | ArcGIS for Desktop It seems like it is not possible to format data attributes that are used as dynamic text. Can someone from Esri please confirm.
Thanks,
Marc