If you have send in your application form and made your payment for your SES Special series number plate you should be hearing from the Department of Transport very soon in fact your letter should be in the mail. Friday I pickup my plates and they look great.
One thing I would bring to your attention is make sure you can remove your old plates. Have a screw driver with you as you have to do this yourself.
If you plan to remove the old plates at the Licensing Centre, it may pay to free the fixing screws with the aid of CRC or WD 40 etc prior to leaving home. Some new model cars use nylon screws on the rear number plates and from person experience these are hard to remove and can break.