When Battle for the Cowl #3 makes Dick Grayson the next Batman, it won't make the first time he has taken over the identity of his mentor. Most current readers recall the Knightfall story that led to Dick spending twelve issues in the cape and cowl in a 1994 story line called Prodigal. But that wasn't Dick's first time going by the name Batman, either. Not even close. If you want to see Dick Grayson suit up in blue and gray for the first time, you shouldn't look to his first appearance as Nightwing in 1984. It was way back in 1951, in Batman #66!
In eight separate stories during the Fifties and Sixties, Dick was seen taking on the Batman identity in an imagined future (the first one set it in 1975, which was then quite a ways off). None of those stories were set in continuity, and employed three different gimmicks to put them in the minds of people who were in continuity. In the first such story, Dick Grayson, after disobeying a tactical order from Batman, had a dream about being "Batman II" and having his own Robin (his real son) disobey him, causing Dick's (imaginary) death. The dream-turned-bad was a morality play that convinced Dick to obey orders more precisely.
The second time around, in Batman #119, it was Batman who imagined the story, hallucinating after inhaling the odor of an exotic plant. In his vision, he awoke as an old man decades later, with Dick having graduated to the Batman role (without the "II" suffix) in a story called "Rip Van Batman". There was a Robin in this imagined story, too, although his identity was not discussed. Right after the elder Batman (complete with a gray beard) helped solve a case, he awoke to find himself back in the present.
The third set-up was provided by a series of stories in which Alfred took out his typewriter and imagined the future. The "II" was back in Dick Grayson's title, but his Robin in this rendition was the son of Bruce Wayne and Kathy Kane. This duo debuted in Batman #131 and ran in six stories, battling crime (even the Joker's son) and culminating in Batman #163, when future Dick Grayson ended up romancing future Betty Kane (who naturally graduated to the Batwoman role). As an indication of how persistent the idea of this imaginary future was, note that the last story was in the very last issue of Batman; the "Batman II" stories were only ended when the "New Look" Batman debuted, complete with a yellow oval.
Those stories ended with Bruce or Alfred noting that the butler's fiction could never be published, because it would give away Bruce and Dick's identities, but end with knowing winks and the question posed to the reader if they might actually come to pass some day. Many decades later, Dick finally became Batman in a story that counted -- in Batman #512. With Bruce sidelined with a broken back, Dick suited up for twelve issues, fighting confidence issues leading to a sort of final exam that pitted him against Two Face.
Battle For The Cowl sends Dick on the path towards putting the cowl back on. The preview for issue 3 offers Dick's thoughts: "Bruce ordered me to stay away from the cape and cowl. And I listened... But Bruce underestimated the psychological effect that Batman had on Gotham." It's easy to connect the dots: Dick is reaching his decision.