The Alternate timeline thing

OK, so the Ancient one says that the stones must all be returned to their original place so an alternate timeline isn't created. Well that's what I gathered from what she was saying, unless she was implying that the universe would collapse or something. But even after the stones were returned they had already created a vastly different timeline in which Loki escapes with the tesseract; Gamora, Nebula and Thanos are essentially "killed" from that timeline. There was also a third timeline where Steve Rogers lives out his life in the past, and probably even more timelines (Each time he returned a stone a new timeline would be created presuming that he can only travel through the original timeline. If he could travel between timelines then the number of timelines he creates would depend on which order he returned the stones in).

So unless the Ancient one was ignorant to this, she was happy with screwing with her own timeline for the sake of Dr Strange in another timeline? Am I getting this right?