Two situations trigger this: (1) the specific delivery date you requested is past its selection cut-off (set on the Cut Off Timer page), or (2) all of your upcoming delivery dates are closed or were already auto-selected. In the second case, if you have no active auto-renewing subscription at all, you're redirected straight to the Subscription page to start a new plan instead of seeing a confusing "closed" message — the system assumes those leftover dates belong to a cancelled plan.