Sending an e-mail from a Sales Quote or Sales Order has a different 'from' address as expected. For example, it is that of a service channel.
SAP Cloud for Customer
The sender e-mail address (from) is determined from the sales unit.
If not available in the Sales Unit, then from the owner.
If not available in either of those (1. sales unit, 2. owner) then it will be pulled from the seller.
This is the standard logic and has never changed.
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