Changing Apple ID from shared account without losing data
Hi. My elderly folks share the same Apple ID but have separate ipads and iphones with different stored data on each. They use the same icloud login details, not part of the Apple Home sharing but they have just done it this way as not v technical. They have just upgraded their phones and again both used the same apple ID.
The question is how can they now change to their own individual Apple ID's without losing their individual data?
Mum would essentially need to register for her own Apple ID. But if she backs up data now before this then presumably this will be only accessible by the old shared account (Dad's account). Similarly if she changes Apple ID this will change it for dad also as the account is currently shared, though again not through apple family sharing.
They don't want to pay for the higher data package needed for family sharing and have v low usage.
Is there a way for them to both have their own apple ID but move forward with their own personal data?
The other issue I thought might arise is they have a shared bank account, and so can a bank card be used for multiple apple ID's?
Thanks!!
iPhone SE (2nd generation)