With the Spring '21 release of Pardot, the new ability to "Sync Prospects Safely With Cross-Business Unit Leads and Contacts" should eliminate the need to create duplicate Salesforce Leads/Contacts for each Pardot business unit. 

https://help.salesforce.com/articleView?id=release-notes.rn_pardot_sync_multiple_prospects.htm&type=5&release=230

If rolling out Business Units to an older Pardot org that has functioned as a single Pardot unit for several years, does it make sense to hold off on rolling out business units until this feature is available (to avoid having to clean up duplicate leads and contacts)? Any information on this topic is appreciated.

Thanks!

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