From the Shopify app, tap Store. In the Sales channels section, tap Online Store. Tap Manage themes. Find the theme you want to edit, and then click Actions > Edit code.
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To create a snippet for your delivery date picker:
It’s been quite a while since you first posted your topic, and I hope that in this time, you’ve managed to find a solution. Nevertheless, I’d like to offer a simple suggestion that could benefit you or other community members facing similar challenges in the future.
Consider utilizing the Easify Product Options app as a potential solution. It can assist in seamlessly incorporating a Date Picker option into your products that are currently sold out . Additionally, you can modify the text of the “Add to Cart” button on these product pages to read “Pre-order.”
Here’s a concise walkthrough of how you can set up this solution using the app: