The problem"Pickup available" is not a number.
Shopify's own pickup widget renders a yes/no. It stays green when the item would have to be transferred in first, when the store doesn't track that item, and when the last one is already promised to somebody else's order.
So the shopper drives across town and your team finds out at the counter. And there's no way to say when — the pickup happens whenever it happens.
Both failures are shopper-side. Neither shows up in your reports — the order simply never exists.