In TweenMax 2.x, use TweenMax.staggerTo, first element yoyo repeat first.
https://codepen.io/7up/pen/LYEpRXg
But in gsap 3.x, use stagger attribute, first element start first, but yoyo last. not same result as above.
https://codepen.io/7up/pen/bGNVwJp
How, can I get the same result using gsap 3.x? @ZachSaucier