While we still await official news regarding the return of the second season of Dragon Ball Super, the promotional series Super Dragon Ball Heroes showed us the return in style of Goku and Vegeta Super Saiyan 4, who seem to have definitely exceeded the limits of this form.
Despite the introduction of this new stadium, what surprised fans was the synopsis of the previous episode: "Following their advice, Goku and his companions completely rely on Xeno Goku and Xeno Vegeta for their powers. As soon as they transform an intense red light emanates from the bodies of the Xeno Warriors, which are enveloped by a different aura from those seen previously. How will the battle with the mighty Janemba end ?! "
In fact the scarlet color of the aura has led to suppose that the new transformation into Super Saiyan 4 comes directly from the Super Saiyan God, which would disproportionately increase the power of the form introduced in Dragon Ball GT. In the discussion regarding the 5 reasons why the SS4 should become canon, we have seen how Broly is able to use the power of Oozaru without however taking the form of a giant ape.
This detail, combined with the ability to Goku and Vegeta to transform into Super Saiyan God, could actually bring the new SS4 to Dragon Ball Super. Recall that a new opening for the SDBH anime has been shown, and that perhaps we will see some news for Vegetto.