If you are using the Printify Shipping Calculator, then you don't need to do anything - new shipping rates will be integrated automatically so the changes will be reflected.
However, you may also be using flat shipping rates, or weight/price-based shipping rates for your Shopify store.
Please follow these steps in order to edit these shipping rates in Shopify:
- From your Shopify admin, go to Settings > Shipping and delivery;
- Next to the shipping profile that you want to edit a rate in, click Manage rates;
- Next to the rate that you want to edit, click the "..." button;
- In the drop-down menu, click Edit rate;
- Make any changes, and then click Done;
- Click Save.