With Taskhelper you can post tasks as far in the future as you want! However, since it might be difficult for Helpers to commit too far in advance and situations can frequently change between now and then, we recommend posting a task when your due date is closer.
You can always leave a comment on your task specifying your deadline or change the due date once you've assigned a Helper to a date of your choice. Please keep in mind that as soon as you assign a Helper, the task money is withdrawn from your account and kept safely in our reliable payment system.
For further information on rescheduling a task once it has been assigned, click this link.