Custom App Clip Card registrations take a long time to "process"

Hi Apple Devs,

I'm seeing additional custom app clip card registrations made manually via the AppStoreConnect website that are "received" successfully (so all the registration parts entered fine online) can take anywhere between 24-48 hours to "process" and the finally start showing up on on device for the given registration URL.

1. Am I doing something wrong that causes this delay?
2. Is there some cache somewhere I need to clear somehow to see registrations faster?
3. Why is there such a delay and why is this process and it's finish time so opaque to the developer?

We never know after completing the registration flow for a new App Clip Card when we can expect the App Clip Card to start showing up/working. We just shrug and wait a few days and it suddenly starts working.

TIA