I have seen posts in the past that say you could email the ABEditor and ask him. I suppose you could come back on here with a different email address and a new username. I believe people who have been banned sometimes do the second option!
A couple of years back the server and security were updated - at that time usernames that had gaps in stopped being recognised and Ed very kindly contacted people with alternatives.
Apart from that, I think your personal online security is your own concern, not Ed's
How can you be anonymous to the ed? You have given him your user name and email address as part of the sign up process so he knows the details. I think it's good that any email to you mentions your user name- at least that way you'll know it's genuine.
Anyway, you are anonymous to the extent that the ed doesn't have to know your real name
factor... I think Vitam12 means someone saw his AB user name in an email and he doesn't want them to know who he/she is on here and be able to see what they have written on AB.
Either way, you can't change your user name... you'll have to sign up with a new one via a different email address...