According to Amazon Japan, the 44th volume of the Diamond no Ace manga will bundle an original OVA. This OVA will be an adaptation of the one-shot Kuramochi Youichi Special Bangaihen: OutRun which is a part of the Diamond no Ace: Guide Book. It covers the "moving story of the Kominato brothers" which isn't covered by the television series.
My goal is to watch as much anime as possible. On my profile you will also find a list of seen cartoons & movies. Sometimes I release older anime or sub some things. If you have any questions, just ask!