Customize local pickup on checkout page

[kunkelmiss]

Hello, 

New to GraphQL and functions and wanted to determine the feasibility of our use-case. 

We have two stores couple of blocks apart and we manage two different inventories. Both locations are enabled for pickup however if a customer adds product from both location and select pickup location, they will see 

Your order isn't available for pickup. Enter a shipping address. I was wondering if on checkout page, we could override shopify validation for local pickup and insert our warehouse locations through functions? 

[shammer]

Did you find a solution for this?  Similar issue here where we'd like to call an external system for stock levels at different pickup locations, and surface details in the checkout of what products are available or unavailable in the different pickup locations.  This would enable a customer to either pick the most suitable pickup location or remove the unavailable item(s) rather than forcing delivery.