How can you trigger an Android heads-up notification through a PWA?

I'm currently trialling a PWA that will act as a notification system for employees that are on call.

I've managed to setup push notifications for my PWA through the use of a manifest file to make it downloadable and a service worker to handle the subscribing, retrieval and showing of notifications and I have a server application that makes use of the web push API to send the notifications.

All seems to be working well, however on Android devices, the notifications do not seem to be showing a heads-up notification and instead goes straight to the 'background' notifications. I understand this would typically be handled through a high priority notification channel for native Android apps but is there any way to accomplish this for a PWA application?

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