There is no need to close your position if you'll need someone in the next few months. You can simply update your calendar, and block the dates when you don't need volunteers, so you can plan ahead. You can check here how to do that.
This way you'll always have someone ready to help you out. :)
If you do not know when you'll need another worldpacker, you can close your position by accessing your profile → clicking on “ Volunteer Positions” → “Close Position”.
Once you’re ready to receive volunteers once again, you can reopen your position to start receiving applications. To do that, access your account → click on “ Volunteer Positions” → “Open Position”.