For those who say that time travelling is not cheating, here some food for thought though.
(I'm not actively taking a stance either way).
Animal crossing is a social game that encourages trading.
Items and materials can take a lot of work and or irl time to get.
When someone time travels, they get huge advantages in this field.
Such as being able to time travel back and forth to easily get all the gulliver items multiple times a day.
That could easily take a non time travelling player over a year to do.
So this pushes people who don't time travel out of the online economy.
I've seen this many times myself where people have gone to sell something they have worked really hard on, just to find that it is so common place that it's basically worthless.
As I said, I'm not taking a stance either way on if it should or should not be done, and you can certainly say that the community is not a part of the game so it doesn't count, but I personally can't say time travelling is a completely harmless thing to do that affects no one else