Notification Nos. 49/2003-CE and 50/2003-CE both dated 10.06.2003 which provide full exemption from excise duties to goods cleared from industrial units in the states of Uttarakhand and Himachal Pradesh for a period of ten years from the date of commencement of commercial production.  The exemption is available to new units set up or existing units which have undergone substantial expansion in terms of the said notifications and commence commercial production before the cut-off date, that is, on or before 31.3.2010

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The provisions of these notifications do not place a bar or restriction on any addition/modification in the plant or machinery or on the production of new products by an eligible unit after the cut-off date and during the exemption period of ten years as per the notification. Therefore, it is clarified that in all the above situations, the benefit of the excise duty exemption under the notifications would continue to be available to eligible industrial units.  However the period of exemption would remain ten years and would not get extended on account of such modifications or additions under any circumstances.

See: 939 /29/2010-CX 

Excise duty exemption continuation permits eligible units to modify production while preserving the original exemption period. Notification Nos. 49/2003-CE and 50/2003-CE grant a full excise duty exemption to eligible industrial units for a ten-year period from commencement of commercial production, provided they are new or substantially expanded and commence production on or before the cut-off date. Eligible units may add or modify plant and machinery and commence manufacture of new goods after the cut-off date during the exemption period without losing the exemption, but such changes do not extend or reset the fixed ten-year exemption period.