Time travel has a 4 years forward minimum and a 4 years back minimum. If you’re wondering, I can’t go backward 4 years then come forward 4.5 years. Nor can I go forward 6 years the come back 5.5. The present for me is 1/12/14. So I have to go forward to at least 1/12/18 from today or 4 years back from today. After the 4 year minimum I can add by quarter hour increments if need be. I can return to today or yesterday but not to tomorrow. The past is set and I can not change it. But I can change the future.
Where on earth did you get that from?