late november at&t phone bill

Received in the mail yesterday:
“Dear AT&T Digital Phone Service Customer: We missed the date for mailing your November bill!…We’re continuing to fine-tune our new billing system and have delayed mailing your November bill in order to prepare an accurate bill. Your November bill that you should have received in November will now arrive in mid-December. Don’t worry!” It’s always good to get a letter like that on Dec. 28.