I'm frankly at a loss why you would delete that, after it was obvious that an admin or moderator added it to your sig. It certainly wasn't added because changing sigs is my new hobby. It has also consistently been the rule for everyone who has had a name change over the last three years, and there's no reason to make an exception. If you would like to start a new user name and avoid the sig, you're welcome to do so.
Unbelievable. And if you have the temerity to try a "just wait 'til your father gets home!" attitude with the owner of this web site, you may want to consider spelling "definitely" correctly. It makes the veiled threat that much more effective.