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                                                                   EXHIBIT 10.30

                                CoreComm Limited
                              CoreComm Holdco, Inc.
                              110 East 59th Street
                               New York, NY 10022

                                                                February 5, 2002

NTL Incorporated
110 E. 59th Street
New York, New York 10022
Attention: Richard J. Lubasch

Mr. Lubasch:

         This letter agreement is to confirm that the parties hereto agree that
as of the date hereof, with respect to the 10.75% Unsecured Convertible PIK Note
due 2011, dated April 12, 2001 (the "Note"), issued by CoreComm Limited and
CoreComm Holdco, Inc. ("Holdco") as obligors in favor of NTL Incorporated
("NTL");

         CoreComm Limited and CoreComm Holdco hereby exercise their right under
         Section (9) of the Note such that, following the completion of Holdco's
         exchange offer to the holders of CoreComm Limited common stock to
         exchange their shares of CoreComm Limited common stock for shares of
         Holdco common stock, the convertibility feature of the Note will be
         altered so that rather than the Note being convertible into shares of
         CoreComm Limited common stock, it will become convertible into shares
         of Holdco common stock. At that time, the conversion prices will be
         equitably adjusted by dividing the conversion prices by the exchange
         ratio at the completion of the exchange offer for CoreComm Limited
         common stock (for example, an initial exchange ratio of 1/38.9 and a
         conversion price of $1.00 would result in a new conversion price of
         $38.90 for each share of CoreComm Holdco common stock, as may be
         adjusted from time to time as set forth in the Note), as may thereafter
         be adjusted pursuant to the Note. NTL hereby agrees not to exercise its
         rights to convert the Note into CoreComm Limited common stock until
         August 5, 2002 (unless that right has previously ceased as a result of
         the completion of the exchange offer and the change in the
         convertibility feature). In the event that Holdco does not complete
         the exchange offer for CoreComm Limited common stock by August 5, 2002,
         the conversion feature of the Note will remain into CoreComm Limited
         common stock on its original terms. This agreement is to be governed by
         the laws of the State of New York.

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NTL Incorporated
February 5, 2002
Page 2

Please indicate your agreement with the foregoing by signing below.

                                            Sincerely,

                                            CORECOMM LIMITED

                                            By: /s/ Michael A. Peterson
                                                --------------------------------
                                                Name:  Michael A. Peterson
                                                Title: Executive Vice President

                                            CORECOMM HOLDCO, INC.

                                            By: ________________________________
                                                Name:  Thomas J. Gravina
                                                Title: Chief Executive Officer

Accepted and Agreed:

NTL INCORPORATED

By: ________________________________
    Name:  Richard J. Lubasch
    Title: Executive Vice President