Hi @LAD23, I appreciate your post! Welcome to the Square Community.
Unfortunately payments links do not support pre-orders. It would have to be an item that is on your Square Online site, in order for the pre-order settings to apply.
A workaround is you could always post it on your site and then copy the item page URL to share with your customers, if needed.
I hope this helps a bit! If not, please let me know and I can take another look.
Thank you
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