For the past few years a day in September is called Batman Day. This day was first set aside three years ago to celebrate his 75th anniversary. There will be all kinds of events going on at participating comic book store and other book stores. Not sure if the ones in my area will be doing anything. However think much like last year there will be deals to be had online. Last year I got Batman Eternal Volume 1 and Volume 2 off the DC Comics app for four dollars each. The date for this event is September 17, 2016.
[Update] You have to act fast. Comixology is running a sale covering may comics/graphic novels over Batman’s history. This sale ends on the 19th. You can see the sale > here.
GetBent57 