sellingPlanGroups created_at search query filter isn't working

[appdev2023]

suppose a query like so

sellingPlanGroups(first: 1, query: "created_at:'2023-07-02T04:23:55Z'"){
      nodes {
        createdAt
      }
    }

In my tests, this always returns the nodes as an empty array... even if the date matches the sellingPlanGroup.createdAt exactly.

{"data":{"sellingPlanGroups":{"nodes":[]}}

I can drop the query filter and the nodes will be populated with the sellingPlanGroup matching the createdAt date. 

{"data":{"sellingPlanGroups":{"nodes":[{createdAt:"2023-07-02T04:23:55Z"}]}}

I believe the filter is breaking silently on Shopify's side. The docs don't give any other description. Presumably it is the same as the created_at example in the filter docs. 

[SBD_]

Hey @appdev2023 

Can you DM me store details so I can replicate please?