This would be a limitation of SSIS where the metadata would need to remain static and cannot be changed dynamically. You may need to implement a design where the records are conditionally split so that the respective paths perform either an insert or update. The field ‘address1_city’ would be mapped in the CRM Destination with the action Insert and excluded in the Destination component that has the Update action.
If you have any other questions, please reach out to our Support Team at kingswaysoft.com/about-us/contact-us and we will be happy to help or clarify.