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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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                                   FORM 10-Q/A

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(X)  QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934.

     For the quarterly period ended September 30, 2001.

(_)  TRANSITION  REPORT  PURSUANT  TO  SECTION  13 OR  15(d)  OF THE  SECURITIES
     EXCHANGE ACT OF 1934

     For the transition period from _________________to _________________.

                         Commission file number 1-16089


                               TRENWICK GROUP LTD.

             (Exact name of registrant as specified in its charter)

                                  -------------

         Bermuda                                          98-0232340
(State or other jurisdiction of                           (I.R.S. Employer
incorporation or organization)                            Identification No.)

                     Continental Building, 25 Church Street
                             Hamilton HM12, Bermuda
               (Address of principal executive offices) (zip code)
                                    --------

Registrant's telephone number, including area code: 441-292-4985

Indicate  by check  mark  whether  the  registrant:  (1) has filed  all  reports
required to be filed by Section 13 or 15(d) of the  Securities  Exchange  Act of
1934  during  the  preceding  12 months  (or for such  shorter  period  that the
registrant was required to file such reports);  and (2) has been subject to such
filing requirements for the past 90 days. Yes [X] No [ ]


Indicate the number of shares  outstanding  of each of the  issuer's  classes of
common stock as of the latest practicable date.

                                                      Shares Outstanding
Description of Class                                  as of November 13, 2001
--------------------                                  -----------------------
Common Shares - $.10 par value                           36,859,840


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                           PART II - OTHER INFORMATION


Item 6. Exhibits and Reports on Form 8-K

     (a)  Exhibits

     10.1 First Amendment and Waiver to the Credit  Agreement,  dated as of June
          13,  2001,  among  Trenwick  America  Corporation,  Trenwick  Holdings
          Limited,  the lending  institutions  from time to time party  thereto,
          First Union National Bank, as Syndication  Agent, Fleet National Bank,
          as   Documentation   Agent,   and  The  Chase   Manhattan   Bank,   as
          Administrative Agent.

     10.2 First Amendment to the Holdings  Guaranty,  dated as of June 13, 2001,
          among  Trenwick Group Ltd. and the lending  institutions  from time to
          time party to the Credit Agreement.

     10.3 Second  Amendment  and  Waiver to the  Credit  Agreement,  dated as of
          November  13,  2001,  among  Trenwick  America  Corporation,  Trenwick
          Holdings  Limited,  the lending  institutions  from time to time party
          thereto,  First Union  National  Bank,  as  Syndication  Agent,  Fleet
          National Bank, as  Documentation  Agent,  and JP Morgan Chase Bank, as
          Administrative Agent.

     10.4 Second  Amendment to the Holdings  Guaranty,  dated as of November 13,
          2001, among Trenwick Group Ltd. and the lending institutions from time
          to time party to the Credit Agreement.

     (b)  Reports on Form 8-K

     The  following  report  on Form 8-K was  filed  during  the  quarter  ended
     September 30, 2001:

     Date of Report                 Item Reported
     --------------                 -------------

     July 24, 2001         Press release, dated July 24, 2001, announcing second
                           quarter earnings changes.


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                                   SIGNATURES


Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                               TRENWICK GROUP LTD.



Date:  January 10, 2002             By:    /s/  James F. Billett, Jr.
                                           --------------------------
                                    Name:  James F. Billett, Jr.
                                    Title: Chairman, President and
                                           Chief Executive Officer



Date:  January 10, 2002             By:    /s/ Coleman D. Ross
                                           -------------------
                                    Name:  Coleman D. Ross
                                    Title: Executive Vice President and
                                           Chief Financial Officer