[Setting state inside timeline]

Hello, 

I need to set my react state inside my timeline after first animation ends and then continue with animations:

const tl = gsap.timeline();
      tl.to(pTitle, 1.5, { x: -550 }).setNewState after previous animation.to(pTitle,1.5,{x:150})

so far I could achive it with that: 

 tl.to(pTitle, 1.5, { x: -550 }).add(
        setTimeout(() => {
          //setNewState
        }, 1500)
      ).to(pTitle, 1.5, { x: "-4%" });

is this proper way of implementing this? Or is there "smoother" way of achieving it like with delayedCall() - which is not available in timeline