When you change your primary Destination Email under your Account settings, any previously approved Senders will stay locked with their existing Destination Email and any new Senders that the system does not have a defined destination for will default to your new primary Destination Email. Should you want to change the Destination Email for multiple Senders, just select the desired Senders (using the checkboxes on the left hand side of the table) and then click the three dots “…” above the Sender list to change the Destination Email address for all selected Senders.