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                                                                   EXHIBIT 10.24

                                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 prices 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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      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: /s/ THOMAS J. GRAVINA
                                              ----------------------------------
                                              Name:  Thomas J. Gravina
                                              Title: Chief Executive Officer

Accepted and Agreed:

NTL INCORPORATED

By: /s/ RICHARD J. LUBASCH
    -------------------------
    Name:  Richard J. Lubasch
    Title: Executive Vice President