First, click Manage Borrowers.

It will open this dialog; click the borrower pair you want to move someone from, then click the Move button for the appropriate borrower. It will open this dialog.

The borrower you've selected will have a turquoise background. Click the radio button for where you want to move the borrower.

Click Yes.

Encompass will stop responding to input for a bit while it moves data around. Once that finishes, your loan should look like the pictures below.