Possible Clues:

• Letters and numbers for letters!
• Letters and digits with a mailing address
• End of address
• Letters and numbers which aid mail sorting
• End of address is time to parody in attitude of pretence
• Addressing the bottom line in communication system
• Eg, E ninety eight one TT
• It has letters on numbers and letters on letters
• Eg, E-Nine-Eight One-T-T
• A symbolic address