Hi @Robmobius , I am pleased you have replicated the issue. In a working environment this functionality renders the Hubspot --> Mautic sync unusable in many scenarios as you just cant have a situation where their is a potential to email someone who has got back to a previous campaign (via a different email) unless you maintain duplicate records or do not use their preferred email. Both workarounds have their limitations.
I have just checked through the Plugin Mapping and it is not possible to map the Hubspot Record ID to the Mautic Record ID. If this was possible and then the “Identifier Key” could be changed from Email to ID then that might be a solution. Do you know if there is a way to ask the Mautic development community to take a look at this issue/behaviour to see if it can be improved? - I would be willing to pay something towards having this behaviour “fixed”.