I would say that Overcome by Laura Mvula featuring Nile Rodgers will maybe feature in this year's forthcoming series
While we are still a couple of months away from the next series - they are still to decide what professionals will renew their contracts - I do believe that songs that will become big in the latter half of the year when the series is in progress will be done. This happened last year, with Hello by Adele and Writing's on the Wall (Spectre theme song) by Sam Smith. Both songs were unknown to the general public at the start of last year's competition.
I would also like to bring this up too. When I went to the see the Strictly tour in Glasgow - which I really enjoyed - two David Bowie songs were played: Modern Love during the interval and the (album version) of Let's Dance right at the very end.

I found that very interesting and I did wonder if a Bowie song or two will feature at some point in the new series.