Your client needs to give you a current 8879, not a stale-dated one. Alternatively, why have you been stockpiling that return since October?

You didn't copy the full CD message.  The CD actually prompts you to enter a date in the current year.  Once you do that, the CD will disappear.  In any case, why would you have a return that was signed last year and only being filed now.  If you did do that, that would be considered stockpiling, which is in breach of the rules for ERO.