Hello DE3_6,
We understand that you'd like to switch to a different plan. However, you do not want to lose the music that you currently have. As long as your subscription is not being canceled, you will not lose access to the music that is associated with your account. You can follow these steps to switch your plan:
"Switch your subscription plan
Change your subscription plan
Switch your subscription plan on your iPhone or iPad
- Open the Settings app.
- Tap your name, then tap Subscriptions.
- Tap the name of the subscription that you want to change.
- Tap See All Plans, then follow the onscreen instructions to complete your purchase.
- If you chose a subscription that you can share with family, turn on Share with Family. (Don't see Share with Family? Set up Family Sharing or join a family, then return to your list of subscriptions and turn on Share with Family.) If you don't want to share the subscription with your family, turn off Share with Family.
Switch your subscription plan on your Mac
- Open the App Store app.
- Click the sign-in button
or your name at the bottom of the sidebar. - Click Account Settings at the top of the window. You might be asked to sign in.
- On the page that appears, scroll to Subscriptions, then click Manage.

5. Click Edit next to the subscription that you want to change.
6. Choose a different subscription option.
7. If you chose a subscription that you can share with family, select Share New Subscriptions. (Don't see Share New Subscriptions? Set up Family Sharing or join a family, then return to this page and turn on Share New Subscriptions.) If you don't want to share the subscription with your family, turn off Share New Subscriptions.
Switch your subscription plan on a Windows PC
- On your PC, open iTunes.
- From the menu bar at the top of the iTunes window, choose Account, then choose View My Account.
- Scroll to the Settings section. Next to Subscriptions, click Manage.
- Click Edit next to the subscription that you want to change.
- Choose a different subscription option.
Switch your subscription plan on your Apple TV
- Open Settings.
- Select Users & Accounts, then select your account.
- Select Subscriptions.
- Choose the subscription that you want to change.
- Choose a different subscription option.
- If you choose a subscription that you can share with family members, make sure that you have set up Family Sharing or joined an existing family group."
More details here: How to switch to a different subscription plan
Thanks for posting your question in Apple Support Communities.
Best wishes.