The change-lock is the first setting to fix

Most settings on a booking platform change how something looks. One of them changes how much of your day you actually get paid for. It is a single number, it lives on the service, and it is called the change-lock.

If you sell time in peak hours — a 07:00 training session, an evening colour, a consultation in the busiest slot of the week — it is the first thing to set and the last thing to loosen.

What the setting does

A change-lock window is a period before the appointment in which the client can no longer move or cancel it from the booking page. Set twelve hours on a service and a 07:00 session stops being client-editable at 19:00 the evening before. The booking page simply refuses.

It is not a lock on the appointment itself. Your front desk can still move or cancel anything from the dashboard at any time — because sometimes the right answer is to let it go, and that call belongs to a person who can see the rest of the day.

The arithmetic

Take a 07:00 personal-training session that the client drops at 06:45. Fifteen minutes is not enough time to sell that hour to anybody else, so it is not a cancellation, it is a deletion. The coach is already awake and already at the studio. The slot is simply gone from the week.

A 4 p.m. colour cancelled the same morning is the same event with a bigger number attached: ninety minutes, at your list price, in the part of the day people actually want. Multiply that against your own price list, once a week, for a year. Nobody needs a statistic to find the result persuasive.

Choosing the window

The window should be roughly the time it would take you to resell the slot, not a punishment. A rough shape that suits most schedules:

• High-value, long services — a colour, a full treatment, anything running past two hours: 24 hours. These are the ones you cannot refill on the day.
• Peak-hour one-to-ones — the 07:00, and the 19:00–22:00 block that is booked out weeks ahead: 12 hours, so an evening change cannot kill a morning.
• Ordinary mid-length appointments in ordinary hours: 4 to 6 hours. Long enough to matter, short enough that a genuine emergency is still handled by a phone call.
• Short, cheap, easily refilled services — a trim, a quick check-in: 1 hour, or none at all. Locking these buys you almost nothing and irritates people.
• Free intro sessions and assessments: leave them open. The point of a free assessment is that somebody books it.

Set it per service, not once for the whole account. A salon that locks a fringe trim as hard as a balayage has protected nothing; it has only made itself difficult to book with.

Pair it with card at booking

The change-lock and payment at booking are two halves of one policy, and each half is weaker alone. Card at booking means the slot is paid for before it is held. The change-lock means the paid slot cannot be dissolved on a whim an hour beforehand. Together they are what stands between a peak hour and an empty room; apart, each has an obvious hole in it.

The window is not a penalty. It is the time you would need to sell that hour to somebody else.

What it protects, and what it does not

Be clear about the limit. The change-lock protects the slot. It does not guarantee the revenue, and it is not a deposit — Calendaty has no deposits and no partial holds. A service is charged in full at booking, or it is marked pay-locally and still tracked to the appointment. There is no middle amount to hold.

So the honest description is this: the change-lock is what stands in for a deposit here. Someone who does not turn up still has not turned up. What the window changes is that they can no longer hand the slot back quietly at 06:45 and leave you with an hour you never had a chance to sell — and if they were charged at booking, that hour was already paid for.

Change one number today

Open your highest-value service, find the field that controls how long before the appointment a client can still edit it, and put a real number in it. Then do the same for whatever fills your busiest hour. That is the entire job, and it is worth more than every other setting you will touch this month.