We currently image our checks for customers, showing them only the front side of the check. Will we have to figure out a way to provide the back of the substitute check as an image now as a requirement of Check 21 (our preference would be to continue the status-quo and only show the front)? Has anyone crossed this bridge yet? We'd appreciate any opinions/facts that the group can provide.

You can continue to do as you do today with original checks.

Bob is right, until you decide to process using Check 21 and are creating Sub Checks, you do not have to worry about this.