This article covers what to expect when you switch your web push provider, in either direction:
Switching to Maestra while leaving your old service
To start collecting subscribers you can send web push notifications to from Maestra, you need to stop sending pushes from your old service and completely remove the old service worker from your website.
Integration
Complete every step in the integration instructions provided by your developer.
Then immediately remove the old service worker from your website.
Leaving the old service worker in place alongside Maestra’s will cause conflicts and prevent new subscribers from being collected correctly.
Why you can’t import a token database into Maestra
Web push notifications are sent to a token. A token is the installation of our code (the service worker) in a specific customer’s browser. Other providers have their own service workers, so their tokens don’t work for us.
On top of that, the push payload format differs from provider to provider. For a push to render correctly in the customer’s browser, the code on the website needs to know exactly how we transmit the title, text, and image. Because of this, we can’t import addresses (tokens) from another provider — pushes simply won’t reach them.
How to switch from Maestra to another web push service
If you’re moving in the other direction — from Maestra to another web push provider — keep the following in mind:
- There is no functionality to export tokens from Maestra.
- If the FCM project was created by Maestra, we can’t transfer ownership of it to other users.
You’ll need to create a new project in FCM and collect tokens from scratch. In practice, this just means users need to visit your website again after the new service is integrated, so they can resubscribe through it.
To keep sending pushes through Maestra during the transition, leave our service worker and scripts on your website — except for the Maestra push subscription collection call (webpush.subscribe).
That way, you can continue sending pushes to your existing Maestra subscribers, but new subscribers will no longer be added to Maestra and will instead be collected by your new provider. 
