Default e-mail selection from mail app for individual contacts in iOS

I have a contact with two email addresses (one used for "home" email and one used for "iCloud"; home is listed first, iCloud is listed second), this person does not use the iCloud email as it is an old email address from a old cable company of all things (yikes be careful what email you use for your iCloud... she doesn't know how to change her iCloud email addy; but that's for another time.)

Anyway, my mail app (until recently, which I guess must be due to a recent iOS update) always picked her the "home" email from her contact, when I was writing an email or forwarding an email to her.

However, the mail app now it picks her iCloud email addy as the default when I am composing an email or forwarding an email..... The issue is that iCloud email was from an old cable company from like 11 years ago and that email gets bounced back to me as undeliverable as she no longer has an account with that cable company.... that's how I know the Mail App changed the default email it was using for her... it started bouncing.

Solution: The only way I've found to over come this issue is to open her contact info, scroll to the bottom to select "add to favorites", select the Mail pull down menu, select her "home" email addy.

If anyone can point me to the help page giving info on how she can update/change that iCloud email address from the old cable company to something else, please let me know... Thanks!