No, but you can do this:
Set the time to the next day at 5:57 am as your main character.
Enter, save and exit
Wait 3 minutes and make a new character, do your plot resetting
The day rolls over at 6am so the villager won't put their plot down until then
No.So you will either
1. change 3DS clock to the next day and go in as new character
OR
2. go in as already made character, change time to 5:59am the day they are to plot (("new day" starts at 6am)), save-quit as soon as game loads ((so before 6am)), wait a minute or two ((so it will be past 6am in game)), load with new character.
OR
3. wait until it actually is tomorrow in real life
If you do 2 but do not wait until it does hit 6am in game before loading with new character, even though it would be after 6 after you get off train, the game will still be playing in the day before. Not the new day.
Happy plot resetting!
Now THIS seems like a more helpful method than time traveling forward and forward and forward and forward into the future. Maybe I'll try this method. Thanks for the helpful tip!