Illinois Bell Operations Letter Planning & Engineering CS&E 7.1 October 28, 1988 312 Split / New 708 Area Code (Operations Forces) 1. This letter is issued to provide information about the area code 312 split that will occur November 11, 1988. 2. All prefixes in the City of Chicago will keep the 312 area code. All prefixes outside the physical boundaries of the city will become area code 708. Customers will keep their same seven digit telephone number. 3. This split is necessary because customers in this fast growing area need more telephone numbers than are now available. The split will be revenue neutral. Subscribers will not pay more to make a call that requires eleven digits (1 + Area code + 7 Digits) than they pay for the seven digits presently dialed. Although the split is revenue neutral to the subscriber, it will cost Illinois Bell several million dollars in operating expense. 4. A main 312 Split Committee supported by eight subcommittees is charged with the task of implementing the split. The split will be accomplished with the least customer dissatisfaction possible, without spending more expense money than needed. 5. The Split Committee and subcommittee are identifying the various data bases and processes affected by the split in some way. 6. Due to Alarm Company and Carrier concerns, a "permissive" period will begin on June 1, 1989 in some offices. The permissive peroid will allow either 7 or 11 digit dialing in both area code 312 and 708. This will allow testing by carriers and equipment changes by the Alarm Companies. A schedule is being assembled that will contain the date each office will convert to permissive dialing. All offices in the present 312 area will have permissive dialing before November 11, 1989. 7. After the split date we will continue the permissive dialing peroid for 90 days, until February 9, 1990. The permissive periods are not announced to the general public. At the end of the permissive period a mis-dialed call will go to a special annoucement for each area. The permissive dialing will be in local offices only and may not be provided outisde the present 312 area. 8. Some codes such as 555, 591, and 976 will remain as seven digit codes in both areas. Mobile cellular prefixes will be a seven digit code in one area only and may not always be the same area where the carriers switching machine is located. 9. Three digit codes such as 411, 611, and 911 will all remain as theee digit codes in each area. A call to 411 in either area will provide information for both 312 and 708 areas. 10. The method of achieving permissive dialing will be different in each type of switch. TCN's and detailed instructions will be issued to cover the various types of switches. Many hours of translations and testing are required to attain the permissive dialing. A computer based program has been developed to make tests to the call-through test numbers. 11. Potential problems that may have been identified include remote call forwarding, flexible route and automatic route lists. In most cases Marketing will issue an order to make the required change. 12. Speed call lists, automatic dialers, computer modems and lines that are call forwarded can also become a problem. This is because subscribers may forget to make the needed area code changes. The only known fix for this problem is extensive customer education. 13. Illinois Bell has begun to advertise the date and other information about the split to our subscribers through the media. Bill inserts are being used to alert people about what to expect when the split occurs. Directories distributed late this year will copntain references to and information about the 312 split. 14. Closer to the actual split date, the publicity will be intensified. This will be to alert as many people as possible about the split and its impact. About three.weeks before the split, all employees will be encouraged to use the new 312 or 708 area code whenever appropriate. This will provide as an in service test if any problems encountered are reported. 15. This letter is intended to be shared with all employees of the Operations department. Except information concerning permissive dialing, the contents of this letter may be shared with non- employees such as family, friends, and associates. 16. This letter will be cancelled March, 1990. 17. The oprginator of this letter is xxxxx xxxxxx, (312) 727-xxxx. [Editor's note: Name and number of orignator omitted for lack of relevance. All else is verbatim from intra-company memorandum]