Starlin said that Marvel is currently planning to release this backstory when Avengers: Infinity War releases on Blu-Ray and DVD in August, most likely as an extended cut in the style of The Lord of the Rings and Batman v.
The Blu-Ray and DVD release of Avengers: Infinity War may feature an extended cut of the ensemble superhero movie that could be over three hours in length.
From a purely financial perspective, creating an extended cut of Avengers: Infinity War would be a truly genius move from Disney and Marvel Studios in order to make even more money off of the most successful superhero movie in history.
We will find out if this rumor has an validity to it or not when Avengers: Infinity War releases on Blu-Ray and DVD on August 14th, 2018.