There is no industry standard on how to approach legacy contacts and each company has taken a slightly different approach. For more information and how-to guides:

See Heather Kelly, “How to set up Legacy Contacts for your Online Accounts”, The Washington Post, May 20, 2022.

Special thanks to Naomi Cahn (Justice Anthony M. Kennedy Distinguished Professor of Law, University of Virginia School of Law) for bringing this article to my attention.