Debugger step over resets changed variable value and continues along original path

See attached blueprint.xml routing context file and message#.xml files. 1. Select Debug As>Local Camel Context (without tests) 2. Stepped message1.xml through the entire route. 3. Stepped message2.xml to choice1 (first breakpoint). 4. In Variables View, expanded Messages>Messsage Header to reveal Message Body. 5. Selected Message Body and opened context menu. 6. Scrolled down to quantity element and changed the value from 3 to 2. 7. Clicked OK. 8. Clicked the Step Over button. The debugger stepped to breakpoint on "setHead1" on the original path. 9. In Variables View, checked the quantity element in the message body. It was reset to its original value of 3. After terminating the debug session and cleaning up the project in Project Explorer, I reran the debugger. I followed my previous steps up to step 8. At step 8, I clicked the Resume button instead of the Step Over button, and the debugger/message2 followed the second path (otherwise/else2) as expected. Continuing on with the route, when I attempted to change the value of quantity for message4, the debugger became unstable and terminated the session.