5 Seconds of Summer's "Youngblood" (Capitol) is the new #1 at T40 this week, plus the song is on pace to be the week's Greatest Gainer too, as it moves up to take the crown. Juice WRLD's "Lucid Dreams" (Grade A/Interscope) joins the Top 10. Ariana Grande's "Breathin" (Republic) takes a big jump up inside the Top 25, along with Jason Derulo X David Guetta's "Goodbye" f/Nicki Minaj & Willy William (Beluga Heights/Warner Bros.). Shawn Mendes X Zedd's "Lost In Japan" (Island/Republic) will chart this week, prior to their official impact date.