Batman v Superman: Dawn of Justice is going to be the main launching point of the DC cinematic universe. There are going to be a lot of heroes introduced in the film, and it was all set up by the events which took place in Man of Steel. We previously posted an article on how the consequences of that film propelled the events in Batman v Superman.
In another interview with EW, Henry Cavill is asked about what the ratio of Batman and Superman will be in the film. When answering the question, he makes it very clear that this movie is not a Man of Steel sequel.
“As far as the individual character is concerned, this is not a Superman sequel. It’s more of an introduction to Batman, an opening to Justice League, and an expansion of the world that was created in Man of Steel.”
As for when we will see another solo Superman film, Cavill shares his thoughts saying:
"There’s plenty of time for individual Superman sequels. He’s a tough character to tell. People like the darker vigilante. I think it speaks to the human psyche more easily rather than the god-like being that we can’t really understand. Once we have a more expansive universe we can delve more into the character of Superman and hopefully tell more stories."
It doesn't seem like it's going to happen anytime soon. I imagine we won't see a direct sequel until after 2021. In the meantime, we will see Superman show up in the other DC films like the two Justice League movies being developed, and maybe even more.