<PAGE>

                                                                  EXHIBIT 10.3.6

                                 AMENDMENT NO. 1
                                       TO
                               TIME CHARTER PARTY

                                 April 11, 2005

            Reference is hereby made to the Time Charter Party, dated October
20, 2004 (the "Time Charter"), between Concord Ltd., a company incorporated in
the Islands of Bermuda (the "Owners") and Stena Bulk AB, a company incorporated
in the Kingdom of Sweden (the "Charterers"). Capitalized terms used but not
defined herein shall have the meanings assigned to them in the Time Charter.

            The Owners and the Charterers hereby agree that the provisions of
the Time Charter shall be amended as follows:

            1. The schedule set forth in Clause 47 shall be deleted and replaced
      by the following:

<TABLE>
<CAPTION>
                    "Period                                       Basic Hire
<S>                                                               <C>
1  (Delivery Date - November 10, 2005)                             $ 15,500
2  (November 11, 2005 - November 10, 2006)                         $ 15,765
3  (November 11, 2006 - November 10, 2007)                         $ 16,043
4  (November 11, 2007 - November 10, 2008)                         $ 16,335
5  (November 11, 2008 - November 10, 2009)                         $ 16,642
Option 1 (November 11, 2009 - November 10, 2010)                   $ 16,964
Option 2 (November 11, 2010 - November 10, 2011)                   $ 17,303
Option 3 (November 11, 2011 - November 10, 2012)                   $ 17,658"
</TABLE>

            2. The first and second sentences of the first paragraph of Clause
      48(B) shall be deleted and replaced by the following:

                  "The "Additional Hire" payable for any calendar quarter (other
                  than the first three full calendar quarters following the
                  Delivery Date) shall be equal to an amount calculated as fifty
                  percent (50%) of the Weighted Average Hire for the quarter
                  after deduction of the Basic Hire in effect for that quarter,
                  subject to adjustment as provided in paragraph (D) below. In
                  the case of each of the first three full calendar quarters
                  following the Delivery Date, the "Additional Hire" payable for
                  such calendar quarter shall be equal to an amount calculated
                  as fifty percent (50%) of the Weighted Average Hire for the
                  period from the Delivery Date to the last day of such calendar
                  quarter after deduction of the Basic Hire in effect for such
                  period, subject to adjustment as provided in paragraphs (C)
                  and (D) below. As used herein, the "Weighted Average Hire" for
                  any calendar

<PAGE>

                  quarter (other than the first three full calendar quarters
                  following the Delivery Date) shall be an amount equal to the
                  Average Daily Rate for such calendar quarter multiplied by the
                  number of days in such calendar quarter (excluding any days in
                  such calendar quarter during which Additional Hire is not
                  payable as provided in paragraph (A) above). In the case of
                  each of the first three full calendar quarters following the
                  Delivery Date, the "Weighted Average Hire" for such calendar
                  quarter shall be an amount equal to the Average Daily Rate for
                  such calendar quarter multiplied by the number of days in the
                  period from the Delivery Date to the last day of such calendar
                  quarter (excluding any days in such period during which
                  Additional Hire is not payable as provided in paragraph (A)
                  above)."

            3. The fourth paragraph of Clause 48(B) shall be deleted and
      replaced by the following:

                  "As used herein, the "Calculation Period" shall be the twelve
                  month period ending on the last day of each calendar quarter,
                  except that in the case of each of the first three full
                  calendar quarters following the Delivery Date, the Calculation
                  Period shall be the period from the Delivery Date to the last
                  day of such calendar quarter."

            4. Clause 48(C) shall be deleted and replaced by the following:

                  "Adjustment for the first three full calendar quarters

                  The amount of Additional Hire, if any, payable for each of the
                  first three full calendar quarters following the Delivery Date
                  shall be adjusted by deducting from the amount of Additional
                  Hire calculated pursuant to Section 48(B) for such calendar
                  quarters any Additional Hire paid since the Delivery Date. If
                  after such deduction, the Additional Hire payable for such
                  quarter is equal to or less than zero, no Additional Hire
                  shall be payable for such quarter. In the case of the third
                  full calendar quarter, if the deduction of previously paid
                  Additional Hire as set forth in the first sentence of this
                  Section 48(C) results in a negative amount, such negative
                  amount may be used by the Charterers to reduce future
                  Additional Hire until such negative amount has been reduced to
                  zero."

            Set forth on Annex A hereto is an illustration of the calculation of
Additional Hire pursuant to Clause 48(B) of the Time Charter, as amended by this
Amendment, and the adjustment of Additional Hire for the first three full
calendar quarters following the Delivery Date pursuant to Clause 48(C) of the
Time Charter, as amended by this Amendment. The sample calculation set forth on
Annex A hereto is for illustrative purposes only.

            The provisions of this Amendment shall apply to the calculation of
Additional Hire for all periods commencing on or after January 1, 2005.

                                        2
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            Nothing in this Amendment shall affect the previous calculation and
payment of Additional Hire for the period from the Delivery Date to December 31,
2004.

            This Amendment shall be governed by and construed in accordance with
the laws of England. Except as provided herein, the Time Charter shall remain
unchanged.

            OWNERS                                       CHARTERERS

            Concord Ltd.                                 Stena Bulk AB

            By: /s/ Arthur L. Regan                      By: /s/ Mats Berglund
                -------------------                          -----------------
            Name: Arthur L. Regan                        Name: Mats Berglund
            Title: President and CEO                     Title: Director

                                        3
<PAGE>

                                     Annex A

                      Sample Calculation of Additional Hire
              Pursuant to Clause 48(B) and (C) of the Time Charter

The following sample calculation is for illustrative purposes only and does
constitute part of the Amendment. The Time Charter Equivalent (TCE) rates
presented in the sample calculation below for quarters ending after the date of
the Amendment are hypothetical rates and no assurance can be given that the
actual TCE rates will be the same as these hypothetical rates. The actual TCE
rates for such quarters and the amount of Additional Hire payable for such
quarters may vary from the amounts set forth below and such variations may be
material.

<TABLE>
<CAPTION>
                            AVERAGE      NUMBER OF DAYS    ADDITIONAL HIRE   ADDITIONAL HIRE   NEGATIVE AMOUNT
                            TCE FOR      IN CALCULATION      CALCULATED        AS ADJUSTED     CARRIED FORWARD
              TCE FOR     CALCULATION      OF WEIGHTED       PURSUANT TO       PURSUANT TO       PURSUANT TO
QUARTER(1)   QUARTER(2)   PERIOD(3)(4)   AVERAGE HIRE(5)   CLAUSE 48(B)(6)   CLAUSE 48(C)(7)   CLAUSE 48(C)(8)
----------   ----------   ------------   ---------------   ---------------   ---------------   ---------------
<S>          <C>          <C>            <C>               <C>               <C>               <C>
  4 Q 2004   $  28,000      $  28,000           51           $   318,750         $  318,750      $         0

  1 Q 2005      14,000         19,064          141               251,250                  0          -67,500

  2 Q 2005      14,000         17,078          232               183,000                  0         -135,750

  3 Q 2005      18,000         17,340          324               298,000                  0          -20,750

  4 Q 2005      22,000         17,025           92                63,377             42,627                0

  1 Q 2006      20,000         18,504           90               123,260            123,260                0

  2 Q 2006      17,500         19,377           91               164,333            164,333                0
</TABLE>

------------------
(1)   The fourth quarter of 2004 includes only the period from the Delivery Date
      (November 10, 2004) to the last day of such quarter.

(2)   TCE refers to the Time Charter Equivalent Hire (as defined in the Time
      Charter) calculated for each calendar quarter.

(3)   Average TCE refers to the Average Daily Rate (as defined in the Time
      Charter) and assuming that the vessel is not subchartered by the
      Charterers under a time charter for any period during the Calculation
      Period.

(4)   The Calculation Period for each of the first, second and third quarters of
      2005 is the period from the Delivery Date to the last day of such quarter.
      The Calculation Period for the fourth quarter of 2005 and for all quarters
      thereafter is the twelve-month period ending on the last day of such
      quarter.

(5)   For each of the first, second and third quarters of 2005, the number of
      days by which the Average Daily Rate is multiplied in calculating the
      Weighted Average Hire (as defined in the Time Charter) is the number of
      days in the applicable Calculation Period, assuming that the vessel is not
      off-hire for any days during such Calculation Period. For the fourth
      quarter of 2005 and for all quarters thereafter, the number of days by
      which the Average Daily Rate is multiplied in calculating the Weighted
      Average Hire is the number of days in the applicable quarter, assuming
      that the vessel is not off-hire for any days during such quarter.

(6)   For each of the first, second and third quarters of 2005, Additional Hire
      is equal to 50% of the Weighted Average Hire for the period from the
      Delivery Date to the last day of such calendar quarter, after deduction of
      the Basic Hire in effect for such period. For the fourth quarter of 2005
      and for all quarters thereafter, Additional Hire is equal to 50% of the
      Weighted Average Hire for such calendar quarter after deduction of the
      Basic Hire in effect for such quarter. The Basic Hire in effect for the
      period from the Delivery Date through November 10, 2005 is $15,500 per
      day. The Basic Hire in effect for the period from November 11, 2005
      through November 10, 2006 is $15,765 per day. Accordingly, the Basic Hire
      in effect for the fourth quarter of 2005 is $15,646.90 (the weighted
      average of 41 days at $15,500 per day and 51 days at $15,765 per day).

(7)   For each of the first, second and third quarters of 2005, the amount of
      Additional Hire calculated pursuant to Section 48(B) of the Time Charter
      is adjusted by deducting any Additional Hire paid since the Delivery Date.

(8)   In the third quarter of 2005, if the deduction of previously paid
      Additional Hire results in a negative amount, that negative amount may be
      carried forward and deducted from future Additional Hire payments.