New Horizon Experience. This article describes the New Horizon Experience, which is available now. As of September 28, 2026, New Horizon is the default starting point on a computer or laptop. In the Horizon WebRef mobile apps for Android and iOS, New Horizon is already what you see. If you still have the older layout, choose Switch to New Horizon from the banner or your account menu. You can switch back to Legacy Horizon from that menu any time during the transition.
This article covers Lock Availability While Assigning (Feature #3) on System Settings. Organization administrators use it to decide when an official's Availability Calendar day locks after an assignment. Everyday officials do not open this setting; they only see the lock on their calendar. Use this article when you are choosing a lock rule, turning locking off, or explaining why a day cannot be edited.
Turn it on and choose a rule
Sign in with organization administrator access, then open System Settings. Choose Features & Settings. Search for Lock Availability, or open the Assigning group and find #3 Lock Availability While Assigning.
On a computer, the same row sits in the wider Features & Settings layout.
Turn the feature On, then choose one of the four options in the list next to it. Changes save on their own; you should see All changes saved when the page is done writing.
On a computer, the same four labels appear in that list.
What each option does
When a day is locked, the official cannot change that day on their Availability Calendar. They see a padlock on the day, and a notice such as October 12 2026 has been locked by your officiating organization and cannot be edited. (the date matches the day they tapped). Canceled games do not lock a day. A game's Published or Unpublished status does not change locking; unpublished games still lock under the rules below, so calendars can stay steady while you finish scheduling.
Only if unaccepted or declined locks a day when the official still has an unaccepted assignment, or a declined or turned-back assignment, on that day. After they accept every open offer and any declined work is cleared or rescheduled, that day can unlock again. This is the usual recommended choice when locking is on.
Only if unaccepted locks only while an unaccepted assignment remains on that day. After the official accepts or declines, the day unlocks so they can edit the calendar again. Use this when you want officials to update availability right after a decline.
Permanently once assigned locks the day once any assignment exists on that day (accepted or not). The day stays locked for the official. Only a scheduler editing through Simulation Mode can change that calendar day for them.
Off turns locking off. Officials can always edit their own calendar days (within the usual past and future limits of the Availability Calendar).
In every locking scenario, an organization administrator or assignor can still update that person's calendar for them in Simulation Mode when needed.
What officials see
Officials open Availability Calendar (on a phone the title may read Availability). A locked day shows a padlock. Tapping or clicking that day does not open Advanced Availability; they get the locked notice instead. For the official-facing walk-through, see Why is my availability calendar locked for editing? and Understanding the Availability Calendar.
If you still see the older layout
On the older desktop or laptop System Settings page, Feature #3 still appears in the Features & Settings list. The older option labels read Permanently Once Assigned, Only if unaccepted or declined, Only if unaccepted, and Never. Those match Permanently once assigned, Only if unaccepted or declined, Only if unaccepted, and Off in New Horizon (the last choice is named Off instead of Never). You still choose Save Settings at the bottom of that older page.