Oh, I get it! Now I divided the duration in half and everything worked out. Here's how:
tl.to(charsArr,{duration:0,y:'+='+(curObjText.size*2)})
.to(charsArr,{ease: "power1.out",duration:durationAnimS*0.5,y:'-='+(curObjText.size*2), stagger:{amount:durationAnimS*0.5}}).
to(charsArr,{ease: "power1.in",delay:durationAnimM,duration:durationAnimE,y:'+='+(curObjText.size*2)});
Have I done the right thing? Now the animation takes 0.32 seconds, as it should be (durationAnimS = 0.32)
Thank you very much!!!