SellingPlans FixedPricingPolicy isn't being applied to orders

Hey all,

I’m having an issue with the SellingPlan API, I’ve created a SellingPlan with an initial charge of 20% and a pricing policy of 20% as well, based on my understanding of the API, this should charge 20% of the cost of the item at checkout and take 20% off the final cost upon final charge, however pricing policy is never applied anywhere through the checkout or charging process, could anyone help shed some light on what i’m missing or how this should work?

Below is a sample of the selling plan response from GraphQL, none of these are recurring items

{
    "id": "gid://shopify/SellingPlan/1564967052",
    "name": "Nov 12 - 20% plan 1",
    "category": "PRE_ORDER",
    "options": [
        "Pre-order with deposit"
    ],
    "billingPolicy": {
        "checkoutCharge": {
            "type": "PERCENTAGE",
            "value": {
                "percentage": 20
            }
        },
        "remainingBalanceChargeTrigger": "EXACT_TIME",
        "remainingBalanceChargeExactTime": "2024-11-12T11:20:00Z"
    },
    "pricingPolicies": [
        {
            "adjustmentType": "PERCENTAGE",
            "adjustmentValue": {
                "percentage": 20
            }
        }
    ],
    "deliveryPolicy": {
        "fulfillmentTrigger": "UNKNOWN"
    },
    "inventoryPolicy": {
        "reserve": "ON_FULFILLMENT"
    }
}