In Salesforce integration,
Once initial Fileld Sync was done, Can I re-sync to another Filelds or cancel the sync?
If I must absolutely do so.
Is it possible if asked to support?
It is possible to do, and you'll have to work with Support to do it as they've taken away any capabilities for admins to make the mapping change.
Just so you're aware, the field(s) you want to remap can't be used in any form, smartlist, smart filter, or flow, so make sure the field is removed from all locations before making the request to Marketo Support. I would also make a note of where it is being used prior to you removing it from anywhere so that you can update the forms, smartlists, smart filters, and flows after the field has been remapped.
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