From ARRL News:
To keep member records up to date, ARRL emailed Life Members on June 16 and will be sending a follow-up email in the next few days, asking them to verify their mailing address. Be assured that it is a legitimate request sent from ARRL. Thank you to all those who responded.
If you need to update your address information, call (860) 594-0200, email firstname.lastname@example.org, or respond to the email you received. If your email client does not recognize the text as a link, you will need to cut and paste it into a web browser to access the verification web page.