What is the difference between Time travel and Temporal Do-Over, and why are Angels allowed to change timelines when it's forbidden for Gods?

Question

In Dragon Ball Super, we have seen Trunks traveling across timeline using a time machine and even Zamasu or Gowasu using a time ring. And unlike Gowasu, Zamasu/Trunks have changed events, and this has been depicted as a bad and forbidden thing.

We have also Whis reversing time ("Temporal Do-Over") in the Resurrection F saga and he has even explained that he can reverse time by 3 minutes in case of emergencies.

My questions are:

• What is the difference between Time travel and Temporal Do-Over?
• Why are angels allowed to change timelines but it's forbidden for even Gods?

Answer 1

The Temporal Do-Over isn't sending them back in time. It's rewinding all of time to that point. Since events had to happen to reach the time-rewind, then there is no alternate reality-events gets rewound and start anew as though they never happened. Time-Travel is moving from one point in time to another. However, doing so creates a 2nd reality in which you traveled thru, while the original reality continues as though you never did. With now multiple realities to monitor in the same universe-it would be rather difficult, so why not keep it clean?

Angels themselves are sons and daughters of the Grand Priest, and are also referred to as messengers of Zeno. They are the power-check against Gods of Destruction(hell angels can destroy if they wanted to). The authority being granted for using that power, was given to them by Zeno to use in emergencies(remember, Zeno can see the future). Zeno also gave each of those beings their own specific tasks to complete. Destroyers destroy, angels instruct and guide. If a God needed time reversed, the Angel could decide if it is necessary or not. Checks and balances even in the Dragonball world.