The three-part Calendar Man story come to a conclusion in Batman 385 (July 1985), thanks to Moench, Hoberg, Chuck Patton and Alcala.
By far the biggest problem with this tale is simply that all the encounters between Batman and Robin and the Calendar Man are essentially filler, as everyone waits for him to finally try to kill Robin. Batman wants to keep Robin safe, but even when he has the chance, the Calendar Man passes on trying to kill the boy ahead of schedule.
When the big day finally comes, it is, at least, fulfilling to see Robin take the villain down, rather than Batman.
Aide from that, this is a really good outing for the villain, who is next seen in Crisis on Infinite Earths.