From haveibeenpwned.com:-
Compromised data: Dates of birth, Email addresses, Genders, IP addresses, Passwords, Security questions and answers, Usernames, Website activity
Hack was taken a step further on the weekend, where my account was logged into, the password changed then the email address changed to [email protected]. The email notification of this change included a link to lock the account, so at least the hacker shouldn't be able to use it now. I've also reported the email account to yandex.ru and their IP address (with date and time stamps) to their mobile ISP.