startAt is a legacy property that is really only useful if you want a to() tween to behave as a from() tween as it allows you to specify at which values you should startAt (from).   As Sahil mentioned. using set() and then a to() or just a fromTo() is going handle pretty much any situation you need. I don't think startAt is really necessary for anything these days.   Definitely check out fromTo: https://greensock.com/docs/TweenLite/static.fromTo()   I wasn't entirel