A Family linked account recently signed up to Apple Music for a 3 month free trial, but selected the Individual account option rather than Family, so only that single account has access to the trial.
I want to change the subscription to Family, but don't want it to see that as a purchase "now" and end the free trial.
Some Googling around this found me a Reddit question from 4 years ago (indicates it would carry over), but I'd rather not hang my hopes on old information. Hopefully one of our members has a more recent experience with this.
Best Answer
I contacted Apple Support and they advised that the free trial would carry over.
I can confirm that having changed the subscription that this has worked as expected.