Yes. The music will remain on all platforms that were selected at the time of releasing. So if you released on AMPLIFY+ with Apple Music we will not remove your track from this shop if you downgrade to Free Plan
You can continue to use iMusician, you will pay a 10% commission on your tracks (not 20%).
In essence, yes if commission is all your after then you can absolutely do this.
We hope (of course) that you’ll stay subscribed as the following will also happen:
Your Artist Hub (if you have one) will downgrade to Artist Hub Free version
You’ll also pay commission on YouTube Content ID (if you have it through iMusician).
We’re also planning on releasing a bunch of new features, so we hope that, even if you do unsubscribe and follow your plan above, we can get you back to subscribing