User blog comment:RoyallyBella/Official Season 7 discussion blog/@comment-27648648-20160121023415/@comment-5875378-20160121231049

Season 8 won't be coming out for some time because it takes a while to write the story, design the characters, outfits, and sets, etc. They come out with a new season every other year so the next season won't be until 2017. Season 6 came out the year after Season 5 because it was co-produced by Nickelodeon and so production was quick. Season 7 didn't come out the following year after Season 6 because they did not announce it until Spring 2014 and that is when production began. It would not be ready in Fall 2014 so that is why the season didn't start till Summer/Fall 2015 in most countries. I'd say we might get a trailer around Spring 2017 and it may start in Summer/Fall 2017.