Checkout validation (the date guard)
Updated 19 August 2026
The picker stops most bad orders in the browser. Flare's date guard is the server-side backstop: a Shopify checkout rule that validates the order at the moment of payment, so nothing invalid slips through, not even from surfaces where the picker cannot run.
What it blocks
- Checkout with no delivery date when you require one.
- A selected date that has become invalid since it was chosen. It passed its cutoff, went over capacity, was blocked, or fell inside your minimum lead time.
- Addresses outside your zones, when delivery there is not offered.
The shopper is asked to fix it before paying, so you never receive the broken order.
Where to find it
Open Order management → Controls and select Open checkout settings on the Checkout validation card. Flare takes you to the checkout rule in Shopify.
You can also get there directly: Shopify admin → Settings → Checkout → Checkout rules. Open Flare's rule to see the Delivery Date Guard Settings panel.
Require a date, or allow dateless checkouts
The panel has one switch: Require delivery date before checkout.
- On (the default): a date is mandatory for shippable checkouts.
- Off: checkouts without any date evidence may proceed. Use this if you take orders through the Shop app or other surfaces where the picker does not run, and you prefer dateless orders over blocked ones.
Known-invalid states still block either way. Unserviceable addresses, stale dates, and expired cutoff deadlines are always stopped.
Custom messages
Shopper-facing copy is editable in two places.
In the guard's Shopify settings panel, three fields cover the guard's own messages:
- Delivery unavailable message, shown when delivery is unavailable for the selected address or cart.
- Missing date message, shown when a date is required and none is found. The default is "Please select a delivery date to continue."
- Invalid date message, shown when the selected date is in the past or a cutoff has passed.
On Storefront experience, the Checkout error messaging section covers the checkout picker's own messages, for Address unavailable, Products unavailable, and No shipping options. Leave a field blank to use Flare's default wording.
Write them like a human. "We don't deliver to this postcode yet, see our delivery areas" beats a generic error.
Do I need to configure anything?
No. The guard installs with the checkout picker and follows your existing rules. Touch it only to change whether a date is required, or to reword messages.