Thanks Jason. That makes sense! I was getting confused with the bindings in the SB which is used for the POST. Now the fields are prepopulated with the current values, change the values then submit - all OK. There is no redirection so the page loads again with the fresh values. If I resubmit with new values, the older ones are displayed. Strange things happening here! If I resubmit without changing anything it alternates between old & new values.
Perhaps there should be a redirect to another page after submission.