@Patrick79 - What you want is to set up a temporary minimum stay for a time period in the future. You can make temporary requirements in the your Availability Setting.
1. Go to you calendar view. In the upper right, on the dark bar, you will see "Availability settings". Click that. A drop down will appear
2. Under the "Reservation Preferences", near the bottom of the drop down, you will see "minimum and maximum" stays. Don't be tempeted to put 2 in here now. That will make your reservation requirement for this year be 2-nights minimum starting now. Based on what you said, you want to start next year, so go to the next step
3. Under that is a link for "Add another requirement". Select that. A window will override your screen to "add a requirement".
4. The first option is "During". Use to the carrot to expand the selections. The second to last option is "Specific Dates". Select that.
5. The next set of boxes is for the "between". Select the date you want to start receiving 2 day reservations. You said "next year" so maybe you really mean 1/1/2017. You will need to use the calendar that pops up and use the navigation arrows in the upper right of the drop down to go to the date you want this minimum to start.
6. The end date calendar will immediately show up once you've selected a date. Use the navigation arrows in the drop down to go to the date you want this to stop. Just pick a reasonable date for now since next year you are going to permanently make the requirement for 2 night-stays. This can be explained later. Select an end date that suits you, maybe 12/31/2017.
The box for "minimum" should be highlighted now. Enter 2 in the box.
7. Save.
8. The overwrite screen should disappear and you are back to the calendar view with the Availability settings open and your new requirement should appear. It will say, "During Jan 1, 2017 - Dec 31, 2017, guests stay for a minimum 2 nights".
This will insure that only guests seeking a 2 night or more minimum will be shown your listing to when seeking accommodations in your area in 2017.
You can make the minimum stay 2 days later, using those first boxes I said to bi-pass for now. If you change your mind, you can always use the edit function on the requirement and delete it. All lessons for another day 🙂
Good luck.
Alice