Answer to huis question. sry its kinda complicated

hmm lol no it isnt quite possible, because the most you can ever go back is a day.
It is decided by the international date line. if u r on one side and it is the 16th and you fly round the world to the other side it will be the 15th. And because u cannot fly any further around, you cannot gain anymore time.

The international date line is like the equator. it is an imaginary line, however unlike the equator runs around and the date line runs up and down. it goes between russia and america and through fiji, it isnt exactly straight, so as to avoid confusion on the islands. but it will be the same time on one side as the other, u just have a different day.

Then u have greenwitch, with is a place in england almost opposite the intenational date line.from there u can either be GMT+ or GMT- and those are the time zones. if u r east of green to the dateline u r GMT+ however many hours and if u r west then u r GMT- however many hours. for example australia is east of greenwitch so we are GMT+8 and parts of america are GMT-8 however once u get to GMT+12 or -12 then u reach the international date line and although u have the same time, one is a day ahead and the other is a day behind.

Daylight saving relates to the earths axis and the path around the sun but it is a human concept, like the international date line, and I'll let brigitta explain that.

So that is the explanation and stuff, now u know how earth time works. I'm sorry I just wrote an essay. i am kinda bored.